
    ²²²²²²±  ²²²²²²²²±±      ²²²²²²±   ²²²²²²²²±  ²²²²    ²²²²±±  ²²±±     ²²±±
  ²²±±±±±±   ²²±±±±±²²±±   ²²±±±±±±    ²²±±±±±±   ²²±²²  ²²±²²±±  ²²±±     ²²±±
 ²²±±        ²²±±   ²²±±  ²²±±         ²²±±±      ²²±± ²²±± ²²±±  ²²±±     ²²±±
 ²²±±        ²²²²²²²²±±   ²²±±         ²²²²²²²²±  ²²±± ±±±  ²²±±  ²²±±     ²²±±
 ²²±±        ²²±±±±±±     ²²±±         ²²±±±±±±   ²²±±      ²²±±  ²²±±     ²²±±
  ²²±±       ²²±±          ²²±±        ²²±±       ²²±±      ²²±±  ²²±±     ²²±±
    ²²²²²²±  ²²±±            ²²²²²²±   ²²²²²²²²±  ²²±±      ²²±±   ²²²²²²²²²±±
    ±±±±±±±  ±±±±            ±±±±±±±   ±±±±±±±±±  ±±±±      ±±±±   ±±±±±±±±±±

                                                                      v1.4


                                  D O C U M E N T A T I O N


                                  (c) Marco Vieth, March 1996




-------------------------------------------------------------------------------




Table of Contents:

       1.  Introduction
           1.1  Tips on how you should read this documentation
           1.2  Copyright, guaranty
           1.3  What is a CPC?
           1.4  What does CPCEMU offer you?

       2.  Installation of CPCEMU
           2.1  Files which comprise the CPCEMU package
           2.2  Requirements and installation
           2.3  Hints about memory and soundcards
             2.3.1  Using EMS Memory
             2.3.2  Defining the BLASTER environment
             2.3.2  Defining the ULTRASND environment

       3.  Differences between CPC and CPCEMU
           3.1  Keyboard
           3.2  Loading of Programs, Menus
             3.2.1  Loading from Disk, Menus
                    - The Insert Disk Menu
                    - The File-Selection Menu
             3.2.2  Loading from and saving on cassette
             3.2.3  Loading and saving of snapshots

       4.  Changing the Configuration
           4.1  The setup menu
           4.2  The configuration file
           4.3  Command line parameters

       5.  Data Transfer CPC <-> PC
           5.1  The disk as a media
             5.1.1  The disk transfer program CPCTRANS
             5.1.2  The format- and copy-utility 22DISK by SYDEX
           5.2  The parallel interface
             - The parallel adapter
           5.3  The serial interface
           5.4  Other possibilities

       6.  Sources of Supply, Support, and Acknowledgments
           6.1  Where can I get CPC software ?
           6.2  News, exchange experiences
           6.3  If you have questions or suggestions
           6.4  Other Amstrad CPC emulators
           6.5  Plans for future releases of CPCEMU
           6.6  Acknowledgments
           6.7  Registered trademarks

       7.  Internal Information about CPCEMU
           "Black Box", with its own table of contents


       Appendix:

       A.1  Glossary
       A.2  Bibliography
       A.3  Index


---------------------------





1.  Introduction
ðððððððððððððððð


Welcome to the world of emulators!

What?! You want to know what CPCEMU is, and what you can do with this
strange program that has yellow writing on a blue screen, displaying
"Syntax Error" after every input?


To avoid long searching, here it is:
        CPCEMU emulates an Amstrad CPC 464, 664 or 6128 with many
        extensions. In other words, the program imitates the
        behaviour of the older Amstrad computers on your new PC.

For what purpose?
Well, if you still have no idea, then you will not have any need for CPCEMU.

Some reasons:
        - nostalgia (oh, how nice my good old CPC was ...)
        - better performance compared to the original
        - better environment to develop programs in
        - playing games
        - work (yes, a CPC is good enough for simple word processing)
        - [                                  ] <- insert other reasons
                                                  of your own.




1.1  Tips on how you should read this documentation
===================================================


  You should play around with the online help first, but if you need
  in-depth or more precise information, read on...


  I have tried to arrange the documentation in an orderly fashion. Should
  you still have questions (after reading it several times!), you can
  contact me. You can certainly do so, even if everything is perfectly
  clear to you. See chapter 6 (Sources, Support, ...) on how you can reach
  me.

  In chapter 1 (Introduction) I describe how best to read this
  documentation, who owns the copyright and some things about the CPC in
  general.

  In chapter 2 (Installation) it finally starts. You will be told how to
  install and start CPCEMU.

  Chapter 3 (Differences between the CPC and CPCEMU) deals with features of
  the emulator you should know about, if you are familiar with a real CPC.
  Mainly I will describe keyboard, disks, tapes and snapshots.

  In chapter 4 (Changing the Configuration) I describe how to tailor CPCEMU
  to your needs. Maybe then you will be able to run your favorite program.

  In chapter 5 (Data Transfer CPC <-> PC) you find out how to get your old
  CPC programs onto the PC. Further, the utilities that come with CPCEMU
  are explained.

  In chapter 6 (Sources, Support, and Acknowledgments) you will be told how
  to optain the latest version of CPCEMU and who you can contact should you
  have any questions.

  Chapter 7 (Internal Information about CPCEMU) is for experts only. The
  "official" part of the user manual ends with the previous chapter. I
  describe how one goes about programming an emulator and what you need to
  know to do it. The debug menu of CPCEMU is also explained, which allows
  you to analyze the processor and memory at *any* time during the
  emulation. Casual users should skip this chapter, at least during the
  first reading.

  Appendix A.1 contains a glossary with descriptions of the most important
  technical terms. Appendix A.2 is the bibliography and A.3 the index.



1.2  Copyright, Guaranty
========================

  CPCEMU was developed by (see also section 6.3):

         Marco Vieth
         Auf dem Uekern 4
         D-33165 Lichtenau
         Germany


  CPCEMU is Freeware, which means you can give the program to friends and
  acquaintances for *free*. Archive maintainers are allowed to include
  CPCEMU in their program collections for "downloading". Shareware
  distributors are allowed to distribute CPCEMU, if they only take a small
  fee for copying. Compared to Public Domain, Freeware does not mean that
  it is "free" and you may do anything with it. I still retain the
  copyright.

  All software and documentation is provided "as is" without warranty of
  any kind.


  Although this program is freeware, I would certainly accept any sort of
  support, technical or financial.
  See chapter 6 for more details.



1.3  What is a CPC?
===================

  If you already know what a CPC is, simply skip this section and continue
  reading with 1.4.




  Still here?

  I do not want to go into technical details now, but will rather give you
  a retrospective view so that you may better understand what a CPC is.

  CPC is an abbreviation for Colour Personal Computer. Computers of this
  type were first built in 1984 by the british company Amstrad and sold
  under different names in other countries.
  It was the period of the home computer; Commodore C64, Sinclair Spectrum,
  Atari 800XL, ... when the CPC 464 was unveiled. It had as much RAM as the
  Commodore C64 (namely 64 KB), a built in cassette recorder and Locomotive
  BASIC 1.0. It was followed up by the CPC 664 which had a built-in 3" disk
  drive and a slightly extended Locomotive BASIC 1.1. The CPC 6128 came in
  1985, with 128 KB RAM and nearly the same features as the CPC 664. 3"
  disks were awfully expensive, but more stable than the 5.25" disks
  (nearly as stable as today's 3.5"), and they were noticably faster versus
  tape speed, very unlike the situation with the C64 ...
  All three models were sold with either a colour or a green monitor, which
  had the power supply built in. Later, two or three other models (the CPC+
  for example) were introduced. The BASIC was with nearly 178 instructions
  powerful and fast. One could program graphics, sound and even interrupt
  handling all in BASIC without the use of PEEKs and POKEs. The software
  supply increased dramatically over the years.




1.4  What does CPCEMU offer you?
================================

  The following is a short overview of what CPCEMU offers you. Subsequent
  sections of the documentation will go into more detail.

  CPC graphics in 3 different screen modes (X x Y x COLOURS):
       Mode 0: 180x200x16
       Mode 1: 320x200x4
       Mode 2: 640x200x2
       (With VESA BIOS these graphics can be displayed in resolutions
        ranging from 640x400x16 up to 1280x1024x16, depending on your
        monitor and the VGA card used.)

  Sound: either through the PC-speaker, Soundblaster (3 channels, stereo)
       or Gravis UltraSound (3 channels + noise, stereo)

  Memory:
       ROM: OS, BASIC, AMSDOS, up to circa 13 additional ROMs (with EMS)
       RAM: 64KB, 128KB, up to 576KB Dk'tronics compatible RAM (with EMS)

  Disk: Special disk images, with the extension .DSK

  Cassette: Standard files under DOS, e.g. CPC BASIC- and binary files
       with the extensions .BAS and .BIN respectively.

  Snapshots: You can make memory dumps of running programs in order to
       continue them later. Snapshots have the extension .SNA .

  Speed: On a 386/33 with EMS-memory, CPCEMU is faster than the original.
       A realtime mode allows you to slow down the emulation to exact CPC
       speed. This realtime mode works well on a 486DX2/66.




2.  Installation of CPCEMU
ðððððððððððððððððððððððððð

In this chapter you will learn, how to install and start CPCEMU. Section 2.2
lists some points on why you should be using EMS memory and how to set up
the Soundblaster environment. Full user defined installation with the
configuration file is described later in chapter 4 (Changing the
Configuration).



2.1  Files which comprise the CPCEMU package
============================================

  You have received the CPCEMUxx.xxx package with the following files:
  (I have put the directories in brackets where you will find the files
  after the installation.)

  COPYMATE.ROM   ROM with a copy program (ROM)
  CPC464.BAT     CPC 464 startup file
  CPC464.ROM     ROM (firmware+BASIC) of a CPC 464 (ROM)
  CPC664.BAT     ditto, but for CPC 664
  CPC664.ROM     (ROM)
  CPC6128.BAT    ditto, but for CPC 6128
  CPC6128.ROM    (ROM)
  CPCADOS.ROM    AMSDOS for all CPCs (ROM)
  CPCEMU.CFG     the configuration file for all CPCs (or CPCEMU0.CFG)
  CPCEMU.DAT     data file for CPCEMU
  CPCEMU.DBF     database with pokes
  CPCEMU.EXE     the emulator
  CPCEMU.HLP     the online help, try pressing F1...
  CPCEMU.MSG     the message file (required)
  CPCEMU_D.TXT   German documentation
  CPCEMU_E.TXT   English documentation (this file)
  CPCEMU_F.TXT   French documentation
  CPCPARA.BAS    Locomotive-BASIC program for the parallel adapter (UTILITY)
  CPCPD1.DSK     disk image with some example Public Domain programs (DISC)
  CPCREC.BAS     Locomotive-BASIC program to receive programs (UTILITY)
  CPCT0.BAT      batch file for CPCTRANS.EXE (example) (UTILITY)
  CPCTRANS.CFG   configuration file for CPCTRANS
  CPCTRANS.EXE   transfer program for disk images (UTILITY)
  CPMDISKS.DEF   format definitions for 22DISK (UTILITY)
  FILE_ID.DIZ    archive description for BBSes
  INSTALL.BAT    batch file for installation
  PCPARA.EXE     PC side of the parallel adapter (UTILITY)
  README_D.TXT   German Readme
  README_E.TXT   English Readme
  README_F.TXT   French Readme
  README_S.TXT   Spanish Readme
  ROMGET.BAS     Locomotive-BASIC program for saving ROMs (UTILITY)
  SNA2GIF.EXE    a snapshot to GIF converter: grap your CPC screens...


  The original Amstrad ROMs are included. The Firmware is copyright by
  Locomotive Software; the BASIC is copyright by Amstrad. Amstrad and
  Locomotive have given me permission to distribute the ROMs with CPCEMU.



2.2  Requirements and Installation
==================================

  You will need at least (there is no upper limit of course)
  - PC AT 386 with VGA graphics
  - MS-DOS, possibly with EMS,  or
    Novell DOS (DRDOS)  or
    OS/2 2.x DOS box.
  - If you want to start programs from within ZIP archives you will need
    the program PKUNZIP in your DOS searchpath for extraction.


  The installation itself is very simple:
  Copy the CPCEMUxx.ZIP archive onto your hard disc and decompress it with
  'PKUNZIP CPCEMUxx.ZIP'. Run INSTALL.BAT to create the necessary
  subdirectories. Start CPC464.BAT, CPC664.BAT or CPC6128.BAT depending on
  what CPC you would like to emulate. After the configuration has been
  shown, the well-known yellow and blue CPC opening screen appears.
  You can quit the emulator with F12 and see the online help with F1.
  It is best to try that now, before reading any further ...




  If some errors occur during the configuration, you will be put into the
  so-called debug-menu, which you can exit with 'q' <RETURN>. In such
  cases, it is sometimes useful to redirect the start-up messages into a
  file, e.g. with 'CPCEMU > INIT.TXT'. Then you are able to analyze the
  problem later.



2.3  Hints about memory and soundcards
======================================

  The following will help you if you desire a particulary fast emulation
  or if your soundcard is not recognized correctly.


  2.3.1  Using EMS Memory
  -----------------------

    You should have hardware or emulated EMS on your PC (EMS=Expanded Memory
    System). This speeds up the emulation in a significant way, especially
    with BASIC. Simulated EMS is too slow.
    All you need is EMM (Expanded Memory Manager) supporting the LIM 4.0
    standard (LIM EMS 4.0).

    If EMS usage is possible, a memory count 'EMS xxx Bytes ok.' will
    appear during initialization.
    Otherwise you will see "Sorry, using conventional memory".

    Example under OS/2 2.x (settings for the window):
        EMS_FRAME_LOCATION = auto
        EMS_HIGH_OS_MAP_REGION = 32     (or more)
        EMS_LOW_OS_MAP_REGION = 0       (or more)

    Example under DOS in the CONFIG.SYS file:
        DEVICE=C:\DOS\HIMEM.SYS
        DEVICE=C:\DOS\EMM386.EXE 1024
        ...






  2.3.2  Defining the BLASTER environment
  ---------------------------------------

    In order to hear sound from your Soundblaster you must set the BLASTER
    environment variable properly. Either use the program 'SET-ENV.EXE' (or
    'SBTEST.EXE') included with your soundcard or modify AUTOEXEC.BAT
    directly. In AUTOEXEC.BAT, you should have a line similar to the
    following:
        SET BLASTER=A220 I7 D1 T3

    Where:
      A specifies the base address (0x220)
      I specifies the IRQ (7)
      D specifies the DMA channel (1)
      T specifies the type of the soundcard:
          1 : Soundblaster 1.0/1.5
          2 : Soundblaster Pro
          3 : Soundblaster 2.0/2.5
          4 : Soundblaster Pro 3/Pro 4.0
          5 : Soundblaster Pro (Microchannel)
          6 : Soundblaster 16

    For version 2,4,5 & 6 stereo sound is enabled.

    There are also some more parameters which will be ignored:
      H specifies the 16 bit DMA channel for 16 bit cards (5)
      M specifies the base address of the sound blaster mixer (224)
      P specifies the port address for MIDI (330)



    If you hear no sound, use A388 (instead of A220). This works for
    Media Vision Pro Audio Spectrum 16 and possibly other sound cards
    with SB emulation. It may also work with an Adlib Card.
    (Joe Cotroneo)




  2.3.3  Defining the ULTRASND environment
  ----------------------------------------

    In order to get sound with your GUS (Gravis Ultrasound Classic/ MAX/
    ACE), you must have the ULTRASND environment variable defined.

    Your AUTOEXEC.BAT file should contain the following line:
      SET ULTRASND=220,1,1,11,7

    Where the meaning of the numbers is (in the order shown):

        220 is the base address (0x220)
          1 is the GUS DMA channel
          1 is the SoundBlaster DMA channel
         11 is the GUS IRQ
          7 is the SoundBlaster IRQ

    Important are the base address and the GUS IRQ. All other values must
    be specified in order for the emulation to work properly.




3.  Differences between CPC and CPCEMU
ðððððððððððððððððððððððððððððððððððððð

In this chapter, I describe those features that differentiate CPCEMU from a
real CPC. The section that follows will explain those keys on the keyboard
that have a special meaning during emulation, especially the function keys.
Afterwards you will be told how to load from disk or cassette.



3.1  Keyboard
=============

  Maybe you have already noticed that the function keys of the PC do not
  map directly to those of the CPC. They cause some strange output which I
  will describe below. Or maybe you have been looking for the COPY-key for
  hours...
  All CPC keys are really emulated somewhere, you can be sure of that. Here
  the secrets are unveiled:

  - ALT, ALTgr : COPY on a CPC

  - PAUSE Key : suspends the PC, until it is pressed again. If the function
    keys of the PC do not react anymore, you may have the PAUSE Key
    enabled.

  - Keypad : Depending on the "Num Lock" state, the keypad functions in a
    different way. With "Num Lock" enabled, the keypad represents the
    function keys of the CPC, otherwise it will emulate joystick 0. If you
    want to use an analog PC joystick, you have to calibrate it first. (See
    chapter 4 - Changing the Configuration).

  For completeness:
  - Page up/down: Moves the whole CPC screen.
    (Don't ask me for what purpose.)

  And, of course, the function keys.
  F1  : Online-Help Key. Could be the most important key when you start out.
  F2  : Toggles between the CPC screen (normal view) and  message screen
        (that one with a red border). This screen may show some control
        messages.
  F3  : Insert a disk, see section 3.2.1
  F4  : Toggle sound on/off
  F5  : Load a snapshot (memory dump), see section 3.2.3
  F6  : Save a snapshot, see section 3.2.3
  F7  : Setup menu, see section 4.1
  F8 :  Hard reset, acts like a reset button on a CPC (or switching the CPC
        off and back on again). Use this, if CTRL/SHIFT/ESC does not work
        any more.
  F9  : Reserved for future use
  F10 : Debug menu, explained in chapter 7. If you stumble inadvertently into
        this menu, press 'r' for R)un or 'q' for Q)uit.
  F11 : Reserved for future use
  F12 : Exit the emulator




3.2  Loading of programs, menus
===============================

  In this section you will learn how to load programs from disk, tape or
  snapshots. Certainly the same goes for saving. How to use the menu is
  described, too.



  3.2.1  Loading from Disk, Menus
  -------------------------------

    Under normal conditions AMSDOS (Amstrad DOS) is active, and all file
    instructions use the disk.
    You do not need to insert a real CPC disk into your PC drive every time
    you acces a file (apart from the fact that you may have 3" CPC disks
    only).
    To obtain better speed a CPC disk is contained inside a so-called disk
    image. This file can be located anywhere on the hard disk (or on a high
    density disk).

    Here some BASIC AMSDOS instructions:
    - CAT <RETURN> : displays the catalogue

    - With 'RUN"<filename>"'  you load and start a program.
      You may omit the ending quotation marks. This instruction is useful
      for BASIC programs having the extension .BAS, and in many cases for
      binary programs with the extension .BIN .

      A simple way to run a program:
      1. Input the filename, e.g.  'disc' *without* pressing <RETURN>
      2. Hold down the CTRL key and press cursor-left (the cursor moves
         back to the first column now)
      3. Still hold down the CTRL key and press the ENTER key on the keypad
         (RUN"disc   appears and the program will be loaded)

    - LOAD"<filename>" loads a program without starting it. You can inspect
      BASIC programs with LIST and start them with RUN. Usually binary
      programs will not load with LOAD, but try using the MEMORY instruction
      first, e.g. 'MEMORY &1fff'.

    - SAVE"<filename>" saves a BASIC program. For binary programs you have
      to specify some more parameters, e.g. 'SAVE"<filename>",b,&c000,&4000'
      will save the screen.

    - MERGE"<filename>" is also possible. It merges one BASIC program to
      another already contained in memory.


    Some special AMSDOS instructions are introduced by a vertical dash:
    - |A, |B to select the drive (also possible with |DRIVE,0 or 1)
    - |DIR,"<filename pattern>" to see the directory.
      Important note: Use the following on a CPC 464:
           a$="<filename pattern>" : |DIR,@a$
    - |ERA,"<filename>" erases a file.
      Important note: Use the following on a CPC 464:
           a$="<filename>" : |ERA,@a$
    - |REN,"<new name>","<old name>" to rename a file.
      Important note: Use the following on a CPC 464:
           a$="<new name>" : b$="<old name>" : |REN,@a$,@b$
    - |TAPE  to switch to the cassette. Described in the next section.
    - |DISC  to switch back to disk
    There are some other instructions but they are not so important.



    The Insert Disk Menu
    --------------------

    Until now you can use only one disk, the one already "inserted" in
    the drive. To insert another disk, simply press F3 and the following
    menu appears:

                     Insert_Disk
                     Drive              0
                     Side_Select        0
                     Write_Protected    0

    With the cursor keys <up/down> you can select a line. You can also do
    that by typing in letters (go back with <DEL>). Change numbers with
    the cursor keys <left/right> or with direct input of digits.
    <RETURN> in any line (e.g. the first one) takes the changes. It would
    be dismissed with <ESC>.
    "Drive" is the desired drive (0=A, 1=B); "Side Select" is a side switch
    for double sided disks, it has no effect when using a single sided
    format.
    With "Write Protected" you can mark a disk as write protected
    (0=No, 1=Yes, write protected).


    The File-Selection Menu
    -----------------------

    Now press <RETURN> and a directory of the disk drive appears.
    Select a new disk with the same methods as described above.

    If there is already a disk lying inside the drive you do not need to
    remove it first as in real life. This is automatically done.
    At the bottom of the screen this disk is displayed.

    You will see at most 15 files, if there are more, "[]" appears.
    - <HOME> goes home to the first filename, <END> to the last one
    - <Page up/down> scrolls in pages through the list
    - <RETURN> takes the selected name, <ESC> escapes.
    You can also select names directly by pressing a first letter.

    When using the mouse, click "[]" for <page up>, "[]" for <page down>,
    "[<]" for <cursor left>, "[>]" for <cursor right> and [ok] for <return>.
    Use "[þ]" as <ESC>. Use the right mouse button to mark a line.

    ".." is the parent directory; [A], [B], ... are the available drives.
    Please select only floppy drives with a disk inserted. Otherwise
    you could get some trouble.

    It is also possible to insert disks from inside ZIP archives. Select
    a ZIP archive by pressing <RETURN> and its directory is displayed as a
    normal directory. If you select a file from inside a ZIP archive, it
    is automatically extracted into a temporary file. For this feature
    you will need the program PKUNZIP somewhere in the DOS searchpath,
    or in the CPCEMU directory.
    Temporary files are automatically deleted if they are not needed any
    more. Changes are *not* written to the ZIP archive. If you save
    something on a disk image inside a ZIP file, it will be lost after
    you insert another disk. If you want to change disk images inside
    ZIP archives, extract them before starting CPCEMU.

    How to create disk images from CPC disks that you own is described in
    chapter 5  (Data Transfer CPC <-> PC).




  3.2.2  Loading from and saving on cassette
  ------------------------------------------

    What actually is a cassette for CPCEMU?
    Well, files on cassette are regular files in DOS directories.
    After the '|TAPE' instruction the BASIC instructions for file handling
    use the cassette. But only those starting not with "|".
    Now you can use the instructions described in the section above
    (CAT, RUN", LOAD", SAVE", MERGE") for cassette.
    If you omit a filename, the file selection menu will appear which was
    described in the previous section.
    With SAVE"" you can either overwrite an existing file or create a new
    one by specifying a new name in the last line "(new name)".

    Certainly you can load programs from inside ZIP archives, saving
    is ignored.

    You only get such a fine cassette drive with the emulator!



  3.2.3  Loading and Saving of snapshots
  --------------------------------------

    Snapshots are memory dumps that not only contain the actual memory
    contents but also the internal states of the hardware chips, e.g. the
    processor.
    At any time you can interrupt the running program and save it as a
    snapshot. Later you can load it, and continue at the same position you
    were at when you interrupted it.
    You create a snapshot with F6. Specify the snapshot size, if it is
    64K or 128K. 128K snapshots only make sense if the second memory bank
    is in use. In this case use "128K Snapshot = 1", with the meaning 1=Yes.

    The file selection menu is the same as already described with the disk,
    with the additional comments given for the cassette (3.2.1 and 3.2.2).

    You can reload a snapshot with F5.




4.  Changing the Configuration
ðððððððððððððððððððððððððððððð

In this chapter you will learn how to configure CPCEMU for your needs.
The setup menu is described as well as the configuration file and the
command line parameters.



4.1  The setup menu
===================

  This is the simplest way to make adjustments to CPCEMU. Nevertheless
  this menu does not let you change all settings. To give an example, if
  you want to use additional ROMs you must use the configuration file
  described in section 4.2.

  As already mentioned in the keyboard section, you get into the setup menu
  with F7. The following menu then appears:

       Setting:             Value:   Short explanation:
  -----------------------------------------------------------------------
       ___Emulation
       Emulation_Delay      0
       Emulation_Speed      1
       Interrupt_Frequency  300
       Interrupt_Resume     1
       Realtime             0

       ___Screen
       Colour_Screen        1
       Multimode_Update     0
       Palette_Change       1
       Screen_Offset        0
       Video_Mode           0
       Vsync_Position       5

       ___Sound
       Sound_Enabled        1
       Sound_Device         2
       Sb_Delay             35
       Sb_Delay0            6

       ___Control
       Joy0_Calibrate
       Joy1_Calibrate
       Kbd_Language         0
       Mouse_Enabled        1

       ___Ppi_Settings
       Company_Name         7
       Ppi_50Hz             1
       Ppi_Exp_Signal       1

       ___Misc
       Amsdos_Disabled      0
       Amsdos_Speedup       1
       Break_Mask           3
       Ems_Enabled          1
       Language             0
       Tape_Bypass          1
       CPC_Type             2

       Load_Configuration
       Restart_Emulation
       Save_Configuration
       Poke_Database            database with cheats for games
       Dos_Shell
       Continue


  Select the settings as already described in 3.2.1.


  Emulation_Delay
    This option allows you to slow down the emulation if it is too fast.
    0 means no delay, 100 is a small delay, 300 some more ...

  Emulation_Speed
    0   = slow Z80 emulation
    1   = fast Z80 emulation

  Interrupt_Frequency
    To change the frequency with which interrupts are generated.
    On a real CPC this is always 300 Hertz. If you raise this value
    many programs seem to run faster, but there is less computing power
    between two interrupts. If you own a slow computer you may have
    to lower this value to 100 or 200 sometimes. Possible values are
    18 to circa 600.
    For further information look at chapter 7.

  Interrupt_Resume
    Another of these options one cannot explain without a lot of background
    information. Without EMS (Expanded Memory) this option is 0 which means
    that interrupts can be skipped. Certainly this is not desired, but
    with 1 the emulation is getting too slow. With EMS this option is 1,
    so CPCEMU tries to handle every interrupt.
    Important note:
    It seems that CP/M Plus only runs with EMS and this option = 0 !
    For further information look at chapter 7.

  Realtime
    Enables the realtime CPC. The emulator inserts waits to be as fast
    as a real CPC.

  Colour_Screen
    Emulation of a green or colour screen by changing the palette.

  Multimode_Update
    If programs use several modes simultaneously on the screen, switch on
    this option. Then CPCEMU tries to handle it correctly.
    Per default this option is switched off because it does not work
    properly in all cases.

  Palette_Change
    Set this option to 0 to disable palette changes. This makes sense
    if you cannot see anything because the screen flickers too much.
    If you press the function key F8 to cause a hardware reset, this
    option is reset to 1 automatically.
    Hint: If palette update is disabled and you see completely wrong
    colours, try pressing F2 twice.

  Screen_Offset
    Specify the number of lines the CPC screen should be moved.
    Usually you do not need this option. You get the same effect by
    pressing <Page Up> and <Page Down>. Possible values: 0=no offset,
    up to circa 25.

  Video_Mode
    Set the video mode of the VGA card.
    0 = 640x200x16 (default)
    1 = 640x350x16
    2 = 640x480x16
    and if you have a VESA-BIOS, mostly:
    3 = 800x600x16
    4 = 1024x768x16
    5 = 1280x1024x16
    ...
    WARNING:
    Do use modes >= 3 only, if you monitor supports them!
    If it makes some strange noise, switch it off immediately!
    But this should happen only with old monitors.

  Vsync_Position
    Commonly you will not need this option, but nothing will be damaged if
    you try it. One time during the screen update there is a vertical
    frame fly with a special bit set, the so-called VSYNC bit (vertical
    synchronization). You can define the position, where the VSYNC should
    occur. Possible values are 0 to 5. For further information look at
    chapter 7.

  Sound_Enabled
    Enables the sound output. 1=on, 0=off. You can also press the
    function key F4 instead.

  Sound_Device
    Set the sound output device.
    0 = none
    1 = PC speaker
    2 = Soundblaster
    3 = Soundblaster Pro
    4 = GUS (Gravis Ultrasound), thanks to Ulrich Doewich

  Sb_Delay
    Set the amount of delay after every write access to the soundcard.
    With lower values (e.g. 0) the sound output is speed up. If problems
    with the soundcard occur, use 35.

  Sb_Delay0
    Another delay for the Soundblaster. Do not change it.

  Joy0_Calibrate
    You surely know it from other programs that you have to calibrate the
    analog PC joystick first. Select this setting by pressing <RETURN>,
    move the joystick to the upper left, then to the lower right.
    Then some parameters are displayed. If you always want to use your
    joystick then take note of these parameters and write them in the
    configuration file (see next section). Nevertheless you have to repeat
    the calibration if you change the clock.

  Joy1_Calibrate
    Same as Joy0_Calibrate, but for joystick 1.

  Kbd_Language
    With this option you can select the keyboard mapping for other countries.
    0 = UK, default
    1 = GR, "German-like" keyboard. Unfortunately it is impossible to have
     a full German keyboard because SHIFTed keys cannot be mapped
     to non-SHIFTed. But "Z" and "Y" are swapped, and some other characters
     altered.
    2 = FR, "French-like" keyboard. After the introduction of a German
        keyboard the French will not stand in the rain. Some parts of the
        AZERTY Keyboard are realized. But is has the same problems as
        the German one.

  Mouse_Enabled
    Enables mouse usage in different menus.

  Company_Name
    Company name in the opening screen.
    0 = Isp
    1 = Triumph
    2 = Saisho
    3 = Solavox
    4 = Awa
    5 = Schneider
    6 = Orion
    7 = Amstrad

  Ppi_50Hz
    The CPC can operate with
      0 - 60 Hz, or
      1 - 50 Hz (default in Germany, France)
    During a reset bit 4 of port B PPI is checked and the CRTC is
    initialized properly.
    Let it on 50 Hz.

  Ppi_Exp_Signal
    Some Expansions cards set this signal.
    On CPC 464 set, if a disc drive is connected.
    On CPC 6128 always set.

  Amsdos_Disabled
    Forbids the initialization if the AMSDOS. This is useful if you
    want to load programs from cassette without giving the instruction
    '|TAPE' every time.
    Certainly you could simply make a comment of the ROM_BLOCK line
    for the AMSDOS (with ROM_BLOCK you specify the ROM to load), but
    with the effect that no AMSDOS is present at all.
    Using this option the AMSDOS is still present for some programs.

  Amsdos_Speedup
    Permits an AMSDOS ROM modification speeding up disk accesses.
    This is done by minimizing the motor waiting times, not necessary
    for the emulator.

  Break_Mask
    Only for debugging purposes. With the value 3 from the configuration
    file some errors are suppressed, caused by illegal instructions.
    Do not change this value!

  Ems_Enabled
    Permits the usage of EMS memory (Expanded Memory System).
    If no or not enough EMS memory is available, CPCEMU uses conventional
    memory automatically.
    For further information about EMS consult 2.3.1 and chapter 7.
  Language
    Language for help messages.
      0=UK (English)
      1=GR (German)
      2=FR (French)
      3=SP (Spanish)

  Tape_Bypass
    Permit the usage of the cassette.
    Further information about the TAPE bypass are in chapter 7.

  CPC_Type
    Set desired CPC type
    0 = CPC 464
    1 = CPC 664
    2 = CPC 6128
    3 = CPC 464+ (?)
    4 = CPC 6128+ (?)
    5 = unknown
    In order to use type 3 or 4, you have to supply ROM images in CPCEMU.CFG
    first.

  Load_Configuration
    Load another configuration file saved by "Save_Configuration".
    Some parameters may have no effect until you select "Restart_Emulation".

  Restart_Emulation
    After loading a configuration with "Load_Configuration", you can
    restart the emulation with the new values.

  Save_Configuration
    Save the current configuration.
    Note that you cannot overwrite the master configuration file CPCEMU.CFG.

  Poke_Database
    You are just playing a game you cannot solve? Then try this selection.
    If your game is in this list, you can make it easier by getting
    infinite lifes, e.g. You can also extend the list (CPCEMU.DBF) by your
    own pokes. See chapter 7 for a description of this file.

  Dos_Shell
    Open a DOS shell with much free memory, which you can exit with 'EXIT'.

  Continue
    Take the values and continue with the emulation.
    You get the same effect by pressing <RETURN> in any line with a value.





4.2  The configuration file
===========================

  Now you will learn another way to configure CPCEMU.
  At first CPCEMU reads the configuration file CPCEMU.CFG per default.
  The structure of this file is described so that you will be able to
  use your own ROMs, change the keyboard language permanently, etc...


  Have a look at the file CPCEMU.CFG:

    ;CPCEMU.CFG - The Configuration File for CPCEMU
    ;...
    ;
    ;configuration for CPC 464, 664 and 6128
    ;
    SHOW_CONFIG=1            ;should the configuration be displayed?
    ROM_PATH = ".\ROM"       ;path to ROM images
    ...


  Already with these few lines you get the simple structure:
  Comments start with a semicolon (";"). Options are changed by writing
  a key-word followed by "=" followed by a <value>. The <value> depends
  on the key-word and is either a string or a number. Numbers can be given
  in decimal, hexadecimal ("0x") or binary ("%") notation.

  When knowing the meaning of the key-words, you can adjust the values
  with a text processing system for your own needs.


  You already know most of the keywords from the setup menu.
  First an alphabetical ordered list of all key-words:


  #ENDIF
  #IFCPC
  AMSDOS_DISABLED
  AMSDOS_SPEEDUP
  BREAK_MASK
  COLOUR_SCREEN
  COMPANY_NAME
  CPC_TYPE
  DRIVE_A
  DRIVE_B
  EMS_ENABLED
  EMULATION_DELAY
  EMULATION_SPEED
  HELP_FILE
  INTERRUPT_FREQUENCY
  INTERRUPT_RESUME
  JOY0_CALIBRATE
  JOY1_CALIBRATE
  KBD_LANGUAGE
  LANGUAGE
  MOUSE_ENABLED
  MULTIMODE_UPDATE
  PALETTE_CHANGE
  POKE_DATABASE
  PPI_50HZ
  PPI_EXP_SIGNAL
  PRINTER
  RAM_SIZE
  REALTIME
  ROM_BLOCK
  ROM_PATH
  SB_DELAY
  SB_DELAY0
  SCREEN_OFFSET
  SHOW_CONFIG
  SNAPSHOT
  SOUND_DEVICE
  SOUND_ENABLED
  TAPE_BYPASS
  TAPE_PATH
  TMP_PATH
  VIDEO_MODE
  VSYNC_POSITION


  Following are the meanings of the new key-words:


  - #ENDIF, #IFCPC
    Some control instructions for conditional configuration depending on
    the desired CPC:
      #IFCPC <CPC type> ... #ENDIF
    For <CPC type> all four types from "CPC_TYPE" are valid.
    Consequently you need only one configuration file for all CPCs.
    The batch files CPC464.BAT, CPC664.BAT and CPC6128.BAT set the
    desired type with command line parameters. These are explained
    in the next section.

  - DRIVE_A = "<path+filename>"
    Set the path to disk images. If you use a filename as path, this
    disk is automatically inserted into drive A.
    Section 3.2.1 described Loading and Saving on Diskette.

  - DRIVE_B = "<path+filename>"
    Same as DRIVE_A, but for drive B.

  - JOY0_CALIBRATE = <xcen>, <ycen>, <xdead>, <ydead>
    Define a joystick calibration for your analog joystick.
    Use the values displayed after the joystick calibration in the
    setup menu (see section 4.1).
    This is a key-word with 4 values. You must always specify all of them.
    4 times zero means not calibrated.

  - JOY1_CALIBRATE = <xcen>, <ycen>, <xdead>, <ydead>
    Same as JOY0_CALIBRATE.

  - POKE_DATABASE = "<path+filename>"
    Set the poke database file (CPCEMU.DBF).

  - PRINTER = "<path+filename>"
    Set the printer file where line printer outputs are collected.
    It is cleared at every emulation start.
    After quitting the emulator, you can send it to your printer
    with 'COPY <filename> prn:'.

  - ROM_BLOCK = <ROM-number>,  "<filename>", <ROM-position>
    Describe what ROM should be loaded and where.
    Repeat this line for every ROM you want to load.
    The maximum number of ROMs is circa 20, if you use EMS.

    - <ROM-number> is the number assigned to the ROM, that means
      it is selected by 'OUT &DF00,<ROM-number>' .
      Possible values are:
        0       : Foreground ROM (e.g. BASIC)
        1 - 251 : Background ROMs. On a CPC 664/6128, the ROMs
                  1-15 are automatically initialized during reset
                  (on a CPC 464 only 1-7).
                  The AMSDOS ROM has always the number 7.
        255     : Lower ROM (e.g. OS; has only in emulator this
                  number).
    - <filename> is a file in the directory ROM_PATH, which
      contains the ROM.

    - <ROM position> is naturally 0. If a file contains more ROMs, this
      is the desired ROM position 0, 1, 2, ...
        ROM_BLOCK = 255, "CPC6128.ROM", 0
        ROM_BLOCK = 0  , "CPC6128.ROM", 1
      The lower ROM and the foreground ROM are loaded one after another
      from the same file.

  - ROM_PATH = "<path>"
    Set the path to ROM images. In the configuration file this path
    is set to ".\ROM". The ROMs itselfs are defined with the key-word
    ROM_BLOCK.

  - SHOW_CONFIG = {1, 0}
    Permits the display of the configuration overview when starting the
    emulator.

  - SNAPSHOT = "<path+filename>"
    Set the path to snapshots. If you specify a snapshot file as path name,
    this snapshot is automatically started.
    Look at section 3.2.3 for more details.

  - TAPE_PATH = "<path>"
    Set the path to tape files. In the configuration file this path is
    set to ".\TAPE".
    Look at section 3.2.2 for more details.

  - TMP_PATH = "<path>"
    Set the path for temporary files. They are mainly needed if you
    select a file from inside a ZIP archive and CPCEMU needs to
    extract it with PKUNZIP.




4.3  Command Line Parameters
============================

  As you know from other programs, it is also possible with CPCEMU to
  use command line parameters. But currently there are only a few of them.


  Execute CPCxxx.BAT with the following options:
       /f       : use the fast mode (default)
       /s       : use the slow mode
       /d       : use the debug mode, described in chapter 7
       /x       : disable EMS usage
       /c <file>: specify another configuration file, overriding the
                  default CPCEMU.CFG. See section 4.2.
       /t <type>: set the desired CPC type 464, 664 or 6128 with
                  /t 0, /t 1 or /t 2 respectively.
       /h       : displays a help screen

  The option "/d" is automatically used, if an unknown option was specified.
  Instead if "/" you can also use "-" known from UNIX.




5.  Data Transfer CPC <-> PC
ðððððððððððððððððððððððððððð

What can you do with a good emulator when you do not have any programs for
it or if you do not see any possibility to get programs from a CPC across
to the PC?
In chapter 6 (Supply, ...) some ftp sources are listed where
CPC software can be found.
This chapter deals with the data transfer of CPC software to the PC.
Some utilities for the different possible methods of doing this are
described (disk, with parallel or serial interface).




5.1  Disk as a media
====================

  This is the simplest way to get CPC software across to the PC. You only
  need a CPC with a second drive of the correct size. Correct size means
  that the disks must also fit in your PC drive. (If not, you could still
  try to connect a 3" drive to your PC.) The PC is persuaded to recognize
  the CPC formatted disk using a utility to read the CPC formatted disks.
  This utility is called CPCTRANS.



  5.1.1  The disk transfer program CPCTRANS
  -----------------------------------------

    I have developed CPCTRANS to create disk images from CPC disks.
    Standard CPC formats as well as double sided Vortex formats are
    supported.
    CPCTRANS is not intended to transfer copy protected formats!
    When calling CPCTRANS without parameters you will get a short
    overview.
    CPCTRANS is similar to the DOS COPY-instruction:
    'CPCTRANS <source> <destination> <options>'.
    Examples:
    'CPCTRANS B: DISK1.DSK' copies the disk in drive B to the disk image
    DISK1.DSK. If it does not exist, it is created.
    'CPCTRANS DISK1.DSK B:' writes the disk image back to the disk in
    drive B.

    The first command only runs for the DATA format.
    For other formats you have to use an option:
      /f 0    : DATA format (default)
      /f 1    : DATA format, double-sided
      /f 2    : SYSTEM format
      /f 3    : SYSTEM format, double-sided
      /f 4    : VORTEX format, double-sided
      /f 5    : unknown, CPCTRANS tries to detect it
      /f 6    : +3DOS
    Note the space between "/f" and the number.
    When using the double sided DATA- or SYSTEM-format, you can select
    the side A or B in the disk menu (3.2.1).

    When writing back a disk image, the disk in the drive must have
    the same format! For simple formats you can use 22DISK, described
    in the next section.

    For copying the B-side of a disk, use the option "/s 1"
    With 'CPCTRANS B: DISK1.DSK /s 1' only the B-side of the disk is
    copied, with 'CPCTRANS DISK1.DSK B: /s 1' it is written back.

    The option "/v" turns on "verify", so CPCTRANS checks if the copy
    is correct. That is indeed a bit slower but increases security.

    The option "/t <count>" sets the number of tracks to copy.
    Normally it is 40 tracks, only for the VORTEX format it is 80.

    The option "/q" (quick format) is a feature with which you can format
    a disk image, instead of copying data onto it. Nevertheless you have
    to specify a valid drive as first parameter, even if it is not used.
    Example:
    'CPCTRANS a: SYSTEM.DSK /f 2 /q' formats SYSTEM.DSK as a disk image
    with SYSTEM format.



  5.1.2  The format- and copy-utility 22DISK by SYDEX
  ---------------------------------------------------

    This program is available as shareware. With correct definitions you
    can use nearly all CP/M formats!
    Unfortunately just the CPC formats are not included with the evaluation
    copy of 22DISK. Therefore I have defined the formats in the file
    CPMDISKS.DEF. You will find them in the UTILITY subdirectory.
    What can you do with 22DISK?
    You can transfer single files back and forth between DOS and non-DOS
    formats, format disks and so on.
    Copy the CPC files into the TAPE directory. Read section 3.2.2 for
    an explanation how to load them.



5.2  The parallel interface
===========================

  If you own a CPC without second drive, you can do the data transfer
  over the parallel interface.

  If you own a CPC without a second drive, you can do the data transfer
  over the parallel interface. The original idea came from Gilles Molinari,
  he had also written some Turbo Pascal programs. But maybe you belong to
  the group of users, who do not have a Turbo Pascal compiler on their CPC,
  so you could not do much with the Pascal source. Therefore I have
  rewritten the utilities in Locomotive BASIC, and extended it by adding
  the direction PC->CPC.
  Thus it is possible to transfer files back and forth between CPC and PC!
  The CPC and PC are coupled together via their parallel interfaces.

  If you own a CPC 6128 with Centronics connectors and compare them with
  a printer you will note that CPC and PC fit together excellently when
  using a standard PC printer cable! But do not do that now, please read
  further.
  It seems that only Schneider CPCs have Centronics connectors. If you
  have an Amstrad CPC 6128 with simple edge connectors or a CPC 464,664,
  use the diagram at the end of this section.

  First you have to jump over two hurdles:
  1. constructing a simple adapter
  2. input a short program into the CPC

  Wait!   Do not skip the rest!

  Both steps are really simple, because
  1. is possible without soldering     and
  2. is indeed very short (about 30 lines BASIC)

  To step 2.
  The program you need calls CPCREC.BAS and is in the UTILITY directory.
  It is saved in ASCII, so you can send it to your printer without
  problems and type it into your CPC.
  It does its job like a thin rope sent through a pipe in order to
  get a thick cable through it.
  Here, the thin rope is CPCREC.BAS which receives files from the PC.
  With this little utility you get CPCPARA.BAS (the thick cable) over
  to the CPC. With CPCPARA.BAS you can receive and transmit. Then you
  will not need CPCREC.BAS any more.
  On the PC side you use PCPARA.EXE, also included in the UTILITY
  directory.

  But before you input CPCREC.BAS, have a look at step 1:


  The parallel adapter
  --------------------

  You need an adapter between the PC printer cable and the PC printer
  connector.
  This goes easiest with a RS-232 wiring box, which has a 25pin D-Sub
  male (plug) and a 25pin D-Sub female (socket) connector.
  By plugging short wires into the box you can realize any possible
  connection between both sides. Usually such a box is used - as its
  name already says - for adapting RS-232 interfaces. Serial connections
  do not function at the first, you know.
  We use the adapter the other way round, that is, the plug is for the PC
  side and the socket for the printer cable.

  Plug it together now:

        Plug for the PC printer-         Socket for the printer cable
        connector (left side):             (right side):

               Pin 2     ---------------       Pin 11
               Pin 10    ---------------       Pin 8
               Pin 11    ---------------       Pin 1
               Pin 12    ---------------       Pin 7
               Pin 13    ---------------       Pin 6
               Pin 15    ---------------       Pin 5
               Pin 19    ---------------       Pin 19


  As you see, you do not need all the 25 wires, only 7 of them.

  Although the wiring box is cheap if you buy it from a electronic
  mail-order company, you can get it even cheaper by using a jumper box.
  Then you have to solder the wires. The cheapest way is to buy a 25pin
  D-Sub plug, a 25pin D-Sub socket, a box and some wires.

  Now I presume you have connected the computers with the adapter and
  CPCREC.BAS on your CPC.
  What now?

  1. On the CPC :  Run CPCREC.BAS (after you have saved it)
  2. On the PC  :  Run 'PCPARA /s CPCPARA.BAS'

  Now it gets exciting, if no error messages appear on the PC screen, all
  is OK, the file is on the CPC.

  If the PC does not send anything and reports an error message the
  connection may be incorrect.
  If it is sending ("Sending block xx"), but some error messages appear
  occasionally, your PC may be to fast or to slow. The direction
  PC->CPC is very time crucial, you know.
  On my 386/33 I must not have EMS memory installed, otherwise it is too
  slow. On a very fast computer it could be necessary to use the turbo
  switch.
  Use the program under plain DOS, not OS/2 or Windows.

  If it does not run at all, send me a note.
  In the meantime you can type in the program CPCPARA.BAS which is
  a little longer. The direction CPC->PC runs always, also under OS/2,
  because it is nearly the same as printing. The PC behaves like a printer.

  I assume that you have CPCPARA.BAS on your CPC now.
  Transfer files from CPC to PC in the following way:
  1. On the PC:  Run 'PCPARA /r'.
  2. On the CPC: Run CPCPARA, select S)end and input every file you want
     to transmit. (Run 'PCPARA /r' for every file you want to transmit,
     CPCPARA runs in an endless loop.)


  Thus, use PCPARA in the following way:
  - PCPARA /r : start PCPARA in receiving mode
  - PCPARA /s <file> : sends <file> to the CPC, if you use 'TRM:' as
    file, you will get a terminal.

  All programs in the UTILITY directory display an overview about its
  options if you call them without any parameters.


  WARNING:
  Even if the construction is very simple, I cannot guarantee that you
  do not damage anything. If your CPC printer-port is damaged afterwards,
  it is a pity and rather an unfortunate accident. Perhaps it would be
  also damaged if you had simply connected a printer.
  For example, I know a former CPC user whose keyboard did not work
  properly any more one day. After the repair he was told that he
  should not plug the joystick in while the computer is switched on!
  (Well, I do so always ?!?)

  To come back:
  I have built the adapter successfully. And have even sometimes
  "forgotten" to insert the adapter in the connection and have had no
  problems.





  Diagrams by David Chapeau, if your CPC has no Centronics connectors:

   34 <- - - - - - - - 18      \
   ______________________      |
  |   ________________   |     |
  |  |________________|  |   - | ---> Printer Connector (Female) to CPC
  |______________________|     |
                               |
   17 < - - - - - - - - 1      |
                               |
     ||||||||||||||||||        |
     ||||||||||||||||||        \
     ||||||||||||||||||         >   "CPC 6128 to DMP 2160" Cable
     ||||||||||||||||||        /
     ||||||||||||||||||        |
                               |
   1 - - - - - - - - > 18      |
  ________________________     |
  \    ______________    /     |
   \  |______________|  /    - | ---> Centronics Connector (Male)
    \__________________/       |
                               |
   19 - - - - - - - -> 36      /



   18 < - - - - - - - - 1      \
  ________________________     |
  \    ______________    /     |
   \  |______________|  /    - | ---> Centronics Connector (Female)
    \__________________/       |
                               |
   36 <- - - - - - - - 19      |
                               |
     ||||||||||||||||||        |
     ||||||||||||||||||        \
     ||||||||||||||||||         >   PC Parallel Adapter
     ||||||||||||||||||        /
     ||||||||||||||||||        |
                               |
   1 - - - - - - - - > 13      |
  ________________________     |
  \  ..................  /     |
   \  ................  /    - | ---> Sub-D Connector (Male) to PC (LPT1)
    \__________________/       |
                               |
   14 - - - - - - - -> 25      /


   13 < - - - - - - - - 1      \
  ________________________     |
  \  ..................  /     |
   \  ................  /    - | ---> Sub-D Connector (Female)
    \__________________/       |
                               |
   25 <- - - - - - - - 14      |
                               |
     ||||||||||||||||||        |
     ||||||||||||||||||        \
     ||||||||||||||||||         >   RS 232 "Wired Box"
     ||||||||||||||||||        /
     ||||||||||||||||||        |
                               |
   1 - - - - - - - - > 13      |
  ________________________     |
  \  ..................  /     |
   \  ................  /    - | ---> Sub-D Connector (Male) to PC (LPT1)
    \__________________/       |
                               |
   14 - - - - - - - -> 25      /



   Printer    Centronics   Centronics      Sub-D        Sub-D        Sub-D
  Connector    (Female)      (Male)      Connector    Connector    Connector

      1 ---------  1            1 ---------  1           11 ---------  2
            .                         .                   8 --------- 10
            .                         .                   1 --------- 11
            .                         .                   7 --------- 12
     17 --------- 17           14 --------- 14            6 --------- 13
     18 --------- 19           19 --------- 19            5 --------- 15
            .                  21 --------- 20           19 --------- 19
            .                  23 --------- 21
            .                  25 --------- 22
     34 --------- 35           27 --------- 23
                               29 --------- 24
                               30 --------- 25
                               31 --------- 16
                               32 --------- 15
                               33 --------- 18
                               36 --------- 17



  CPCPARA -> PCPARA (v1.1) transfer speed:

  Times to transfer a block of 0x4000 Bytes from CPC to PC with the
  parallel adapter:

  Source on CPC:                bytes/s:        bit/s:
  -----------------------------------------------------------
  File from floppy disk:        1600            12800

  Block from memory:            2240            17920

  Block from memory, no ints.:  2445            19560
  (poke &b941,&c9 on CPC 6128)

  The block sending was controlled in BASIC (inside CPCPARA):
  defstr a:a="test.$$$":call sstr,@a
  a=string$(&80):for i=1 to &80:call sstr,@a:next:call sbyte,0:stop


  You can read further information about the parallel adapter in chapter 7.



5.3  The serial interface
=========================

  If you own a serial interface for the CPC, you can certainly use it
  for data transfer to the PC.



5.4  Other possibilities
========================

  There are some more fantastic ways to get the software onto the PC.

  - Connect the 3" disk drive to the PC. Some (older) models should fit to
    a 5.25" connection.

  - With a detour over the the Spectrum+3: read the 3" disk on the
    Spectrum+3, convert it in the Spectrum format and use a utility
    to read it on the PC. This utility comes with the Spectrum emulator Z80
    by Gerton Lunter.

  - When is was necessary to get the ROM yourself, someone told me about
    his way:
    He took the ROM chip out of the CPC and inserted it instead of the VGA
    BIOS. With a small program he was able to read the contents.

  - Maybe you will find another way?




6.  Supply, Support, and Acknowledgments
ðððððððððððððððððððððððððððððððððððððððð

In this chapter you will read where to get CPC software and whom to ask in
the case of questions. Furthermore, I mention some other Amstrad emulators.


6.1  Where can I get CPC software?
==================================

  This is no problem if you have access to the Internet.
  As for Spectrum emulators, a number of "anonymous" archives exist
  where you can get CPC software via FTP or WWW.


  FTP
  ---

  - ftp.nvg.unit.no:/pub/cpc, thanks to Arnt Gulbrandsen for
    creating the site, and to Noel Llopis to maintain it,
    one of the biggest archives for CPC programs;
    send what you have in /pub/cpc/incoming

  - sunshine.informatik.uni-wuerzburg.de:/pub/joscho/cpcemu
    mirror of ftp.nvg.unit.no. Any questions, remarks and additions to
    joscho@informatik.uni-wuerzburg.de
    If you have problems connecting to Norway you can try this.

  - ftp.ibp.fr:/pub/amstrad, thanks to Remy Card, all questions about
    this site should be directed to roussin@blaise.ibp.fr
    All the files comes from 'Genesis the 8bit generation BBS' (see
    below),

  - ftp.demon.co.uk:/pub/cpm, thanks to Paul Martin
    specific amstrad CP/M related files
    Paul Martin (pm@nowster.demon.co.uk) will send anyone, who can give
    him proof that they own an original Amstrad CP/M Plus disk, the binary
    ROM images of his "CP/M Plus ROMs" for free.

  - oak.oakland.edu : /Simtel/msdos/emulator/cpcemu14.zip

  - other Simtel mirrors:
    ftp.ibp.fr : /pub3/pc/SimTel/msdos/emulator/
    ftp.demon.co.uk : /simtel/msdos.
    ftp.uni-paderborn.de


  WWW
  ---

  - Amstrad Action homepage at http://www.futurenet.co.uk/

  - http://www.cm.cf.ac.uk/User/K.E.W.Thacker/Amstrad/index.html


  BBS
  ---

  - Aspects (2:250/107) : +44 1617920260, in United Kingdom, sysop Dave
    Gorski, V32b, CPCEMU v1.2, programs (mostly in basic),

  - Genesis the 8bit generation (2:320/220) : +33 1 39 50 54 11, in
    France, up to VFC, sysop : Emmanuel Roussin.
    last versions of emulators, qwerty and azerty 6128 ROMs, freeware,
    shareware, PD, disk zines, pokes, solutions, demos and a few
    commercial games (with the permission of their respective authors).
    For the moment, there are about 29,5 Mo of zipped programs. For fido
    users, you can file request ALLFILES.ZIP, and then what is
    interesting you.

  - Razormaid (2:2471/6009) : +49 711 4204329, in Germany, up to V32b
    and Zyxel, sysop : Thorsten Mitschele also known as Kangaroo in the
    CPC scene, it has the same files as Genesis, with some delay.

  - ZNODE 51 : + 49 89 961 45 75, in Germany, from 15:00 to 3:00 CET
    (MEZ), up to V32b, CPC files

  - Beavis'n'Butthead BBS 2453/407, Germany




6.2  News, exchange experiences
===============================

  Do you always want to have the latest version of CPCEMU?
  Do you want to be informed if a new one is released?

  Meanwhile we have set up a newsgroup especially for the CPC!
  It is called

     comp.sys.amstrad.8bit.

  Here you will find discussions about CPCs (and also CPCEMU), and
  you can talk about your experiences with CPCs.

  There is an FAQ (frequently asked questions) available to this
  newsgroup.

  If you cannot read the newsgroup for any reason, write me an email
  saying that you want to be on the mailing list. Then you will be informed
  about CPCEMU news.

  You will find my address in the next section.
  Certainly you can also use normal mail to ask me (or David, see below),
  but please do not forget the return postage.

  If you send me a contribution, I feel obliged to send the latest version
  to you at least one or two times.




6.3  If you have questions or suggestions
=========================================


  Then you can write directly to me:

       Marco Vieth
       Auf dem Uekern 4
       D-33165 Lichtenau
       Germany

       Phone: (...)05292/1366 (only on week-ends)

       Internet: ali@uni-paderborn.de

       As you have probably already gathered while reading the Internet
       address, I am studying Computer Science at the University of
       Paderborn. I am in my 11 semester (WS 95/96).



  In case you speak or write English (I presume so 'cause you're reading
  this) you also can write to David Cantrell:

       David Cantrell
       116, London Road
       Bexhill-on-sea
       East Sussex
       TN39 4AA
       England

       Phone: +44-1424-221015

       Internet: david@integration.co.uk


  David offered to help a little to answer the "pile of letters".
  He has scanned firmware manual for the CPC, so everyone can get it
  in an electronical form.




  Although this program is Freeware, I would certainly accept any sort of
  support, financial or technical.
  (30-50 Deutschmarks would be appropriate.)
  (That is around 20-33 US$ or 13-21 British pounds.)

  Even if you send no money, I normally respond to all letters and try
  to keep in mind all suggestions (I am sure David will do the same).
  So do not hesitate to send your comments.



6.4  Other Amstrad CPC emulators
================================

  At the beginning of 1994 I thought that CPCEMU was the only emulator
  for the Amstrad CPC. Now I know of three other:

  - SIMCPC:
    Presumably the first CPC emulator written.
    CPC Emulator for PC/XT/AT   (c) 1989, 90 by GHE, Aachen.
    It is only black and white, but with additional ROMs;
    only a "beer humour".

  - CPC2PCxx:
     In development since October 1993 by Paco Lopez (Spain), and
     Is available from some sites now. It is written completely in
     protected mode and uses the same disk format as CPCEMU.

  - CPE:
    In development by Bernd Schmidt. By using a special 50 hertz
    screen mode, some colour blocks are exactly reproduced.
    A special 256-colour CPE2 shows exact colour blocks with more
    than 50 hertz.
    Also supported: Multi modes, overscan.
    Latest version: v5.0.



6.5  Plans for future releases of CPCEMU
========================================


  - overscan
  - improved multi modes
  - screen centering in higher video modes
  - fast hardware scrolling
  - US keyboards have no "<>", ALTgr
  - simulate the expansions-port of the CPC
  - load CPC disks directly
  - load CPC tapes directly (over printer port or Soundblaster card)
  - transfer whole disk images with the parallel adapter
  - volume control for the Soundblaster
  - improved sound (maybe with noise)
  - digiblaster emulation
  - customizable joystick keys
  - use mouse as joystick
  - auto detection of .SNA and .DSK
  - emulate the expansion port

  Maybe this is never done since I have to write my dissertation first
  and do some "real" work...



6.6  Acknowledgments
====================

  - Special thanks to Juergen Weber, not only for many hints and
    suggestions, but especially for the fast Z80 emulation from
    his CP/M emulator ZSIM.

                Juergen G. Weber
                Wiesentalstrasse 1
                74523 Schwaebisch Hall
                Federal Republic of Germany

                email: weberj@dia.informatik.uni-stuttgart.de


  - Also thanks to Bernd Schmidt. Because Bernd wrote his own emulator,
    we have had the same problems many times. Only if you try to write
    such an emulator yourself can you imagine, which details cause problems.
    There is no CPC documentation available, which gives a whole
    specification. Most parts of the CPC behaviour are detected by
    experiments with a real CPC.

  - Thanks to Ulrich Doewich for including Gravis UltraSound sound output
    in the emulator and reading through the documentation. Ulrich wrote
    a similar tool like CPCTRANS. Look out for CPDREAD which can read also
    copy protected disks.

  - Thanks to Emmanuel Roussin for his untiring engagement for the CPC.
    He did the essential steps for setting up the newsgroup and lent me
    his Multiface II for months, so that I could include in the emulator
    somehow.

  - Thanks to Arnt Gulbrandsen for his JPP source, where I found
    ideas for the keyboard handler and the joystick routine.
    By the way, JPP is a very good Spectrum emulator.

  - Thanks to Martin Zacho for supplying a joystick routine.

  - Thanks to Fernando J. Echevarrieta Fernandez for pointing out first
    that version v0.8 did not emulate a CPC 664.

  - Thanks to Gilles Molinari for his transfer program for the parallel
    adapter.

  - Thanks to Paul Martin for correcting the English documentation for
    version 1.0.

  - Thanks to Mark Haigh-Hutchinson for his engagement in making programs
    from the company Vortex public domain.

  - Thanks to Martin Young for his outstanding ideas about emulating a Z80.

  - Thanks to Linh Hsiesh for many ideas for improvements, most of which
    should have been incorperated by now.

  - Thanks to Fred Harris for writing a letter to AMSTRAD about the ROMs.

  - Thanks to Amstrad, especially to Cliff Lawson for allowing me to
    distribute the BASIC ROM. Amstrad retains the copyright.

        Amstrad plc, Brentwood House,
        169 Kings Road, Brentwood,
        Essex CM14 4EF

  - Thanks to Richard Clayton from Locomotive for allowing me to distribute
    the Firmware ROM. Locomotive retains the copyright.

  - And thanks to the many users for sending me suggestions or having
    ideas. Without them CPCEMU would hardly have reached version 1.0

  - (Please excuse my English.)




6.7  Registered trademarks
==========================

  CP/M, CP/M 2.2 and DRDOS are trademarks of Digital Research.
  MS-DOS is a trademark of Microsoft.
  IBM PC, PC-XT, PC-AT and OS/2 are trademarks of International
    Business Machines.
  CPC, AMSDOS by Amstrad,
  BORLAND C, TASM (Turbo Assembler) by Borland,
  22DISK by SYDEX
  Soundblaster by Creative Labs
  ...





------------------------------------------------------------------------------



7.  Internal Information about CPCEMU
ððððððððððððððððððððððððððððððððððððððð


This chapter gives some background information and answers the question,
"WHY shall I do this or that now?"
The powerful debug menu is also described. You will also find the structures
of disk images and snapshot files.
This information is not intended for CPCEMU users without knowledge of
what is inside a CPC. Maybe it will be useful sometime.
I have put this information at the end, even after the trademarks, in an
attempt to show its "relative insignificance".
If you have no fun reading unintelligible sentences and unarranged
information, do not read further!
Skip directly to the Appendix.



WARNING: Go on reading at your own risk !





7.1  Table of contents for chapter 7
====================================

  7.2  Internal overview of CPCEMU features
    7.2.1  The Z80 CPU (The Processor)
    7.2.2  The Gate Array (The "Co-Processor")
    7.2.3  The PAL (Programmable Logic Array)
    7.2.4  The CRTC 6845 (Cathode Ray Tube Controller)
    7.2.5  The PIO 8255 (Programmable Input Output)
    7.2.6  The PSG AY 3-8912 (Programmable Sound Generator)
    7.2.7  The FDC 765 (Floppy Disc Controller)
    7.2.8  The Centronics printer interface

  7.3  The Debug menu
    - Overview of the debug menu
    - Preliminaries
    - Overview of the commands
    - Manipulation of registers

  7.4  Memory management
    7.4.1  Another time: EMS configuration
    7.4.2  How the Banking is done?

  7.5  ROM modifications
    7.5.1  ROM bypass for the cassette
    7.5.2  AMSDOS ROM modifications

  7.6  Miscellaneous
    7.6.1  Another time: The configuration file
    7.6.2  The parallel adapter
       - Direction CPC->PC
       - Direction PC->CPC
    7.6.3  CPCTRANS

  7.7  Structure of selected CPCEMU files
    7.7.1  Disc images
       - The Disc Information block
       - The Track Information block
    7.7.2  Snapshot files
    7.7.3  AMSDOS header
    7.7.4  Poke Database

  7.8  Internal history




7.2  Internal overview of CPCEMU features
=========================================


  How compatible is CPCEMU really?



  7.2.1  The Z80 CPU (The Processor)
  ----------------------------------

  + All Z80 instructions are emulated, including so-called illegal ones.
    You have the choice between a slow Z80 emulation written in C and a
    fast Z80 emulation written in assembler by Juergen Weber.
    With the COCPU technique, every Z80 instruction is
    emulated simultaneously by the slow and the fast version,
    so it gets very slow, but by comparing the registers after
    each instruction many errors are found. Obviously this was
    only used during program development.
    You can activate the slow emulation in the debug menu.
  + Additional instructions 'ED FC xx' only the emulator knows.
    Among them the user break 'ED FC FC  USER &BCFC'.

  - No exact timing of the instructions



  7.2.2  The Gate Array (The "Co-Processor")
  ------------------------------------------

  + All 32 colours of the CPC (27 different ones)
  + All three screen modes (X x Y x COLOURS):
        mode 0 = 160x200x16
        mode 1 = 320x200x4
        mode 2 = 640x200x2
  + ROM banking (16KB OS, 16KB BASIC, 16KB AMSDOS and additional ROMs)

  - Colour beams flicker



  7.2.3  The PAL (Programmable Logic Array)
  -----------------------------------------

  The PAL is logically at the same address as the gate array but
  in hardware separated from it.

  + RAM banking (128 KB, up to 576 KB) with EMS or conventional memory.
    With emulated EMS, the blocks are mapped by the hardware, so the speed
    is OK. CPCEMU gives you a Dk'tronics compatible RAM expansion
    with up to 576 KB.

  - Without EMS, RAM banking is very slow, since memory blocks must be moved
    around in the PC memory. Besides you have only 128 KB RAM.




  7.2.4  The CRTC 6845 (Cathode Ray Tube Controller)
  --------------------------------------------------

  + Screen base and offset for hardware scrolling
  + Several screen sizes from 0x0 to 80x25 with CRTC registers 1 and 6.
  + Different character sizes (1..7) with CRTC register 9
  + Multi modes (they use some other registers)

  - Overscan is not yet supported



  7.2.5  The PIO 8255 (Programmable Input Output)
  -----------------------------------------------

  + Keyboard (connected to the PSG)
  + VSYNC emulation: A bit which is set between two interrupts during a
    screen refresh. You can change the position.
  + The cassette is very fast, a ROM bypass allows access to any DOS file.

  - VSYNC bit is set too long
  - Cassette ports are not emulated, so most of cassette copy programs
    which access the ports directly do not run.


  7.2.6  The PSG AY 3-8912 (Programmable Sound Generator)
  -------------------------------------------------------

  + Either through the PC speaker (awful, since 3 channels are
    multiplexed into one and the volume cannot be changed)
    or a Soundblaster card. Only the Adlib compatible FM part of the
    soundcard is used.

  - No digital-sound or too slow.
    The noises form the PSG have no equivalent on the Soundblaster,
    so they are not emulated.


  7.2.7  The FDC 765 (Floppy Disc Controller)
  -------------------------------------------

  + All necessary FDC commands to control two drives A and B
    (including sector read/write, seek track, read sector-ID, ... ;
    format track is ignored)
    Very flexible disk formats (up to 18 sectors per track).
    Including double sided formats, e.g. VORTEX.

  - Complicated copy-protected formats are not supported.



  7.2.8  The Centronics printer interface
  ---------------------------------------

  + Printer output also with 8-bit printer patch, to a file defined
    by PRINTER.




7.3  The Debug menu
===================

  The complete register set of the CPU is displayed and can be modified.
  You can "dump" the memory, disassemble or modify it. You can load or
  save areas in memory. And the most interesting thing:
  You can single-step through programs!
  (Similar to a real debugger.)

  Overview of the debug menu
  --------------------------

  R)un T)race S)tep  A)ssem D)ump I)nput  L)oad saV)e  M)ode  F)ast Q)uit
  AF=0000 BC=0000 DE=0000 HL=0000 IX=0000 IY=0000 SP=0000 PC=0000 IR=0000
  AF'=0000 BC'=0000 DE'=0000 HL'=0000 IFF1=0 IFF2=0 IMD=0  NZ NC PO P
  0000 : 01 89 7F       LD BC,&7F89
  -f->

  The first line displays the available commands, use the capitalized
  letters.
  The next two lines show the actual values of the Z80 registers.
  The next one disassembles the actual instruction at PC position
  and the last is a prompt waiting for your input.
  ('f' indicates that you are using the fast CPU.)


  Preliminaries
  -------------

  Parameters in special brackets are optional [opt].
  Use only hexadecimal values, e.g. <address> = 0000-ffff
  "<ret>" indicates that you are in a special mode. You may press
  <return> to continue. <String><Return> leaves this mode
  (use e.g. b<return>).
  Commands are letters, mostly followed by an optional address.
  Between the letter and this address must be a blank or tab.
  Without an address, PC (program counter) is assumed as default.


  Overview of the commands
  ------------------------

  R)un:
  r [<address>] : starts emulation from PC or an optional address.
    Examples:
    -f-> r      starts emulation from PC
    -f-> r 100  sets PC to 0x100 and starts emulation

  T)race (trace into):
  t [<address>] : executes only the actual displayed instruction.
    Use <return> to continue in this mode, and so on.
    <string><return> goes back to normal mode.
    All single-step-commands are executed by the slow CPU (even if
    "-f->" is displayed), since there is no counter in the fast CPU
    any more.

  S)tep (step over):
  s [<address>] : executes the next instruction.
    Rather all instructions, until PC is equal to the following
    instruction. This can take a long time e.g. after a 'Ret'.
    In this case F10 helps (as usual).
    All single-step commands are executed by the slow CPU (even if
    "-f->" is displayed), since there is no counter in the fast CPU
    any more.

  A)ssemble (actually disassemble):
  a [<address>] : disassembles the next 16 instructions.
    Use <return> to continue in this mode, and so on.
    <string><return> goes back to normal mode.

  D)ump:
  d [<address>] : shows an hex/ASCII dump of the following 256 bytes from
    address (or PC).
    Use <return> to continue in this mode, and so on.
    <string><return> goes back to normal mode.

  I)nput (modifying memory):
  i [<address>] : shows the actual memory address with its current
    value, which you can take by <return> or change by <hex-value>
    <return>.
    Leave this mode by using an invalid number like '-1':
    -1<return> .

  L)oad (loading a program):
  l [<address>]  : prompts you for a filename <name> and loads it
    from the directory TAPE_PATH to <address>
    An AMSDOS-header is recognized.
    If you press <Return> after the filename prompt, the well-known
    file selection menu appears ...
    Examples:
    -f-> l<return> demo<return>         :
        loads file 'demo' to the actual PC
    -f-> l a000<Return> myprog<Return>  :
        loads file 'myprog' to address 0xA000

  saV)e (saving a program):
  v [<address>]  : prompts you for a filename <name> and the
    length of the memory block. This block is saved from <address>
    (or PC), as binary file in the directory TAPE_PATH, which
    includes an AMSDOS header.
    Example:
    -f-> v<return> demo<return> 4000<return>    :
        saves file "demo" from PC with length 0x4000.

  M)ode (changing the display mode):
  m : Changes display mode: register display, instruction
      disassembling on/off.

  F)ast (selecting the type of emulation):
  f : Flips between the fast Z80 emulation (developed in assembler
    by Juergen Weber, default) and the slow one (written in C).
    The prompt toggles between "-f->" for fast and "-s->" for slow.
    All r, s, t commands refer to the selected type of emulation.

  Q)uit (leaving the program):
  q : quits the emulator.


  Manipulation of registers
  -------------------------

  In addition to the one letter commands you can change register
  values with the syntax:               '<register>=<hex-value>'
  Examples:
  - af=345        : set register AF to 0x0345
  - pc=a000       : set program counter to 0xA000

  You can also write '<register><space><hex-value>'.
  You can modify all displayed registers, i.e.
  AF, BC, DE, HL, IX, IY, SP, PC, IR, AF', BC', DE', HL',
  and also IFF1, IFF2 and IMD.





7.4  The Memory Management
==========================


  7.4.1  Another time: EMS configuration
  --------------------------------------

    You need an expanded memory manager supporting the LIM 4.0 standard
    (LIM EMS 4.0). This memory manager must supply extended EMS-pages in any
    region, as CPCEMU will look for 6 physical pages on continuous addresses.
    If EMS usage is possible, a memory count 'EMS xxx Bytes ok.' will appear
    during initialization.

    You were told to use the following settings under OS/2:

        EMS_FRAME_LOCATION = auto
        EMS_HIGH_OS_MAP_REGION = 32     (or more)
        EMS_LOW_OS_MAP_REGION = 0       (or more)

    What does that mean?
    Low region is for EMS pages in conventional memory. If CPCEMU
    is to use such pages, use at least 6*64KB = 84KB.

    High region is for EMS pages above 640K, additional to the
    standard frame of 64KB. Use at least 2*16KB = 32 KB.


    For DOS, you were told to include the following lines in your CONFIG.SYS:

        DEVICE=C:\DOS\HIMEM.SYS
        DEVICE=C:\DOS\EMM386.EXE 1024
        ...

    Modify the 1024, depending on the available memory of your computer.

    Annotations:
    EMM386 supplies several additional pages in conventional memory.
    The minimum address can be changed with the option /B=<segment>
    (default is 4000).
    With /P<number>=<segment> it is possible to change the segments of
    physical pages.




  7.4.2  How the Banking is done ?
  --------------------------------

    Banking is to enable some home computers to have RAM and ROM at the
    same address. So read is from ROM and write is to RAM. The Amstrad
    CPC has 64K RAM and a 16K ROM at 0-3fff and a second one at c000-ffff:

        0 RAM 0000-3fff
        1 RAM 4000-7fff
        2 RAM 8000-bfff
        4 RAM c000-ffff
        L ROM 0000-3fff
        U ROM c000-ffff

    The main idea is to have different segments and offsets for reading,
    and writing. For every read access, a read offset is added to the
    desired address, and the same is done with a write offset for writing.

                        state 0                 state 1

        block 5   M       L   c                W  0       <
        block 4   M    W  C   c                W  C   c    | swap at
        block 3   M    W  8 b c                W  8 a c    | state
        block 2   M    W  4 b c                W  4 a c    | change
        block 1   M    W  0 b                     L a c   <
        block 0   M       U b                     U a


    (M = conventional memory or physical EMS-pages)

    a = lower ROM enabled,  upper ROM enabled
    b = lower ROM disabled, upper ROM enabled
    c = lower ROM enabled,  upper ROM disabled
    W = lower ROM disabled, upper ROM disabled

    To flip between the two states, the '0' and 'L' block must be
    swapped. For RAM banking a new '0' must be swapped with the old
    one. ROM select is done by copying the new ROM to 'U'.

    With EMS memory, all banking is done by the EMS hardware (or its
    emulation). This improves the emulation speed in BASIC and CP/M
    Plus. Now you understand why 6 continuous physical EMS pages are
    needed; the standard frame with 4 pages is not enough.





7.5  ROM modifications
======================


  7.5.1  ROM bypass for the cassette
  ----------------------------------

    After the '|TAPE' command, or if the AMSDOS ROM is disabled, the
    cassette is addressed. Cassette access is transformed into file
    access in a single directory. This redirection is done by a ROM bypass.
    With 'TAPE_BYPASS=1' you enable the ROM bypass of the tape vectors.
    If CPCEMU finds a known ROM from a CPC 464/664/6128, the ROM is
    modified accordingly. The bypass is necessary if you want to use the
    cassette.

    Some special instructions are implemented in the Z80 emulation. They
    call special functions only supplied by the emulator. They are entered
    directly in ROM, so it is still possible to patch the RAM vectors.

    The following instructions are available:
    ED FC xx  USER &BCxx    (only valid for some RAM vectors)
    Similar to a call instruction to an internal function.
    The following values for xx are legal:
        65      :       CASSETTE INIT (BC65)
        77      :       CASSETTE IN OPEN (BC77)
        7A      :       CASSETTE IN CLOSE
        7D      :       CASSETTE IN ABANDON
        80      :       CASSETTE IN CHAR
        83      :       CASSETTE IN DIRECT
        86      :       CASSETTE RETURN
        89      :       CASSETTE TEST EOF
        8C      :       CASSETTE OUT OPEN
        8F      :       CASSETTE OUT CLOSE
        92      :       CASSETTE OUT ABANDON
        95      :       CASSETTE OUT CHAR
        98      :       CASSETTE OUT DIRECT
        9B      :       CASSETTE CATALOG

    In addition to that, you can use the user break instruction
    ED FC FC  USER &BCFC. It stops the emulation at once.



  7.5.2  AMSDOS ROM modifications
  -------------------------------

    - With 'AMSDOS_DISABLE=1' you forbid the initialization of the AMSDOS.
      Then patching of tape vectors by the AMSDOS ROM is disabled. (So the
      tape vectors are still pointing to tape, although the AMSDOS ROM is
      initialized.) This is necessary if you want continue loading from
      tape after a disc-reset, but without giving the '|TAPE' command
      first.
      (It is done by 'poke &CCF2,&18: poke &CCF3,&05' in the AMSDOS ROM.)
      Sector instructions are not affected, they always address the disk.

    - 'AMSDOS_SPEEDUP=1' enables a AMSDOS ROM modification, which
      minimizes the motor waiting times to render a faster disc access.
      (The things are managed by DOS, so we do not need the delay loops.)
      The following bytes are modified in the AMSDOS ROM:
          poke &C5D4,&01  :'motor load time
          poke &C5D8,&01  :'format track time
          poke &C5D9,&01  :'short wait
          poke &C5DA,&01  :'short wait
          poke &C602,&01  :'only 1 retry on error
          poke &C784,&01  :'fast seek
          poke &C7E2,&01  :'fast seek




7.6  Miscellaneous
==================



  7.6.1  Another time: The configuration file
  -------------------------------------------

    Maybe you remember that comments start with a semicolon ';', and
    can start anywhere on a line. The rest of the line is ignored.
    Blanks, tabs, newlines and ';' are delimiters, and it does not
    matter how many you use.
    Many of the definitions have the syntactical form
    <key-word> '=' <value> {T}
    {T} is a sequence of at least one delimiter.
    Example:
      ROM_PATH = ".\ROM"

    <number> can be given decimal, hexadecimal (with 0x) or binary (%).
    <pathname> may have a length of up to 80 characters and
    <filename> up to 20 characters.

    Some supplementary information to selected key-words:


    BREAK_MASK = <number>               (3)

      For debugging purpose only.
      Some events interrupt the normal emulation. With this flag,
      you can disable such events. Use with caution!
      Leave all bits on except those for such events you do not want
      to occur.
      b2 = 0 -> disable display of port errors (use 3)
      The meaning of the bits can change in future!





  7.6.2  The parallel adapter
  ---------------------------

    First, the construction of the adapter, now with functional description:


    PC  D-SUB   Cent.   CPC             Function
    --------------------------------    ---------------------------
    GND    19 ---- 19   GND             GND
    BUSY   11 <--- 1    -STROBE         Synchro (Data available)
    -ACK   10 <--- 8    D6              |
    PE     12 <--- 7    D5              | Data
    SELECT 13 <--- 6    D4              |
    -ERROR 15 <--- 5    D3              |
    D0      2 ---> 11   BUSY            Synchro (Ready to receive)


    Direction CPC->PC
    -----------------

    Normally the adapter is designed for this direction only. Sending
    on a CPC is on principle the same as printing on a line printer.
    If the PC sets Not-BUSY, the CPC writes a nibble (4 bit of a byte)
    to the port, sets STROBE as sign that the data is there, and clears
    it afterwards. So the PC only needs to clear BUSY (with D0), wait
    for STROBE (his BUSY line) and take the nibble (from the input-lines
    printer->PC), and set BUSY.
    Question: Why not sending 8 bits parallel?
    Answer:
    1. The PC printer port must be reprogrammed for input and I am not
       sure if that is possible on all PCs    and
    2. The CPC has a 7 bit printer port only.


    Direction PC->CPC
    -----------------

    One day I thought about the possibility of sending data in the other
    direction. Unfortunately the CPC has only one single input line at
    the printer port, namely the BUSY signal. So it would not improve the
    situation if you try to design a better adapter for this direction.
    Thus take what you have already and make the best out of it by
    developing a clever protocol.
    A serial interface also has one data line for each direction.
    But, a serial interface uses hardware synchronization, usually with
    a quartz, and both peers have to use exactly the same baud rate
    (e.g. 1200 baud).
    It is hard to do that with software only.
    What should I do?
    The idea is to utilize the speed advantage of the PC over the CPC.
    Each byte is split into 8 bit and transmitted serial, the PC has
    to set the BUSY line accordingly.
    During this 8 bit the CPC gives its maximum speed and the PC has to
    conform with it. The CPC writes a "bit request" with one assembler
    instruction. Now the PC must react promptly by setting the BUSY line
    accordingly the next bit. Since with the following-but-one (?)
    instruction the CPC will read it.
    In order to not disable the interrupts during the whole transfer,
    for every byte a "connection" is established.
    The CPC says "Hey, send something to me!", and the PC answers
    "Ok, I'm waiting until you want it." by toggling the BUSY-line.
    The whole story is protected with timer, so no peer can hang when
    waiting on a signal never sent.
    Thus you can escape the programs with <ESC> or <CRTC>+<BREAK>
    any time.




  7.6.3  CPCTRANS
  ---------------

    Another option not mentioned is "/d 0" or "/d 1". With 1 a special
    double-step mode is selected, on 80 track drives every second track
    is skipped when working with 40 track disks.
    This option should be unnecessary, because CPCTRANS switches
    automatically to double-step when detecting a 5.25" 360 KB disk.

    Normally it is very simple to read or write sectors by using the BIOS.
    But the BIOS cannot handle B-sides of disks with head-mark=0.
    So I had to program the FDC functions myself, with the aid of
    the MINIX source as an outline. Unfortunately the MINIX source contains
    some errors, and the timing in critical sections was done by
    simple delay loops possibly outlined for a 8086 processor.




7.7  Structure of selected CPCEMU files
=======================================


  7.7.1  Disc Images
  ------------------

    Disc image files consist of a 0x100-byte disc info block and for
    each track a 0x100-byte track info block, followed by the data for
    every sector in that track.
    The new extended disk format is intended for some copy protected disks.
    Parts which are new in the extended format are marked with *E*
    (from our Extended DISK Format Proposal, Rev.5).


    The Disc Information block
    --------------------------
    Byte (hex): Meaning:
    00 - 21      "MV - CPCEMU Disk-File\r\nDisk-Info\r\n"
                 ("MV - CPC" is characteristic)
            *E*  "EXTENDED CPC DSK File\r\n\Disk-Info\r\n"
            *E*  ("EXTENDED" is characteristic)
    22 - 2F      unused (0)
            *E*  DSK creator (name of the utility) (no ending \0 needed!)
    30           number of tracks (40, 42, maybe 80)
    31           number of heads (1 or 2)
    32 - 33      size of one track (including 0x100-byte track info)
                 With 9 sectors * 0x200 bytes + 0x100 byte track
                 info = 0x1300.
            *E*  unused (0)
    34 - FF      unused (0)
            *E*  high bytes of track sizes for all tracks
                 (computed in the same way as 32-33 for the normal format).
                 For single sided formats the table contains track sizes
                 of just one side, otherwise for two alternating sides.
                 A size of value 0 indicates an unformatted track.
                 Actual track data length = table value * 256
                 Keep in mind that the image contains additional 256 bytes
                 for each track info.


    The Track Information block (for every track)
    ---------------------------------------------
    Byte (hex):  Meaning:
    00 - 0C      Track-Info\r\n
    0D - 0F      unused (0)
    10           track number (0 to number of tracks-1)
    11           head number (0 or 1)
    12 - 13      unused (0)
    Format track parameters:
    14           BPS (bytes per sector) (2 for 0x200 bytes)
    15           SPT (sectors per track) (9, at the most 18)
    16           GAP#3 format (gap for formatting; 0x4E)
    17           Filling byte (filling byte for formatting; 0xE5)
    Sector info (for every sector at a time):
    18+i         track number    \
    19+i         head number      | sector ID information
    1A+i         Sector number    |
    1B+i         BPS            /
    1C+i         state 1 error code (0)
    1D+i         State 2 error code (0)
    1E+i,1F+i    unused (0)
             *E* sector data length in bytes (little endian notation)
                 This allows different sector sizes in a track.
                 It is computed as  (0x0080 << real_BPS).


    Annotations:
    The sector data must follow the track information block in the
    order of the sector IDs. No track or sector may be omitted.
    With double sided formats, the tracks are alternating,
    e.g. track 0 head 0, track 0 head 1, track 1 ...
    Use CPCTRANS to copy CPC discs into this format.



  7.7.2  Snapshot Files
  ---------------------

    Snapshot files consist of a 0x100-byte header and a memory dump.

    The Snapshot header:
    Byte (hex):  Meaning:
    00 - 07      'MV - SNA' (as characteristic)
    08 - 0F      unused (0)
    10           snapshot version (2, former 1)
    11 - 1A      Z80 register  AF, BC, DE, HL, R, I
    1B - 1C      Z80 flags  IFF0, IFF1 (0=disabled, 1=enabled)
    1D - 24      Z80 register IX, IY, SP, PC
    25           Z80 interrupt mode IMD (0 - 2)
    26 - 2D      Z80 register  AF', BC', DE', HL'
    2E           Gate Array: ink number register
    2F - 3F      Gate Array: ink value register (0, 1, ..., 15, 16)
    40           Gate Array: multi configuration register
    41           Gate Array: RAM configuration register
    42           CRTC: address register
    43 - 54      CRTC: data register (0, 1, ..., 17)
    55           Upper ROM number
    56 - 59      PIO: port A, port B, port C, control port
    5A           PSG: address register
    5B - 6A      PSG: data register (0, 1, ..., 15)
    6B - 6C      memory dump size (64K or 128K)
    (the following parameter exist only from snapshot version 2.0 onwards:)
    6D           CPC type where the snapshot was generated
                 (0=CPC 464, 1=CPC 664, 2=CPC 6128, 3 = unknown)
    6E           interrupt number (0..5), the latest interrupt
                 during a screen update cycle.
    6F - 74      6 multimode bytes, thus screen modes (0..2)
                 for the interrupts 0..5.
    75 - FF      unused (0), maybe later for emulator configuration





  7.7.3  AMSDOS Header
  --------------------

    Byte (hex):  Meaning:
    00           user number (0 , possible values 0-15)
    01 - 0F      filename+extension (possibly filled with 0)
    10           block number (0)
    11           last block flag (0)
    12           file type (0=basic, 1=protected basic, 2=binary,...)
    13 - 14      length of block (0)
    15 - 16      load address (0-FFFF)
    17           first block flag (0)
    18 - 19      logical length (0-FFFF)
    1A - 1B      entry address (0-FFFF)
    1C - 3F      free for the user (0)
    40 - 42      real length of file (1-FFFFFF)
    43 - 44      checksum of bytes 00-42
    45 - 7F      unused (random values from sector buffer)

    Annotation:
    A header is found at the beginning of every non-ASCII file. It is
    identified by calculating the checksum.
    Bytes 00-3F originate from the "cassette area", where files were
    divided up into blocks.
    The bytes 12, 15-16, 1A-1B, 40-42, 43-44 are necessary.


  7.7.4  Poke Database:
  ---------------------

  An entry (one line) consists of 7 parts, each surrounded by '"',
  separated by commas.
  1. part number (1 character, 0-F):
     The first entry has number 0 and can be selected.
     If a program needs more than one poke, following entries have the
     numbers 1, 2, ...
  2. Name of program (up to 20 characters)
  3. Description (up to 20 characters)
  4. Type (1 character):
     ('t'=Tape, 'd'=disk, 'a'=all), currently ignored.
  5. Address of poke (4 characters, hexadecimal):
     Specifies the memory location to be modified
  6. Byte for the poke (2 characters, hexadecimal or '??'):
     If '??', you have to input a value, e.g. number of lifes.
  7. Old byte (2 characters, hexadecimal or '??'):
     Allows to check, if the poke modifies the correct environment.
     If the byte at the address differs form old_byte, a warning is
     displayed. There is no check when using '??'.

  Example:
    "0","Devils Crown","inf oxygen","t","863b","00","??"
    "1","","","t","863c","00","??"
    "2","","","t","863d","00","??"

    There are three pokes for the program "Devils Crown", all working
    together. Old values ark unknown so old byte is '??'.
    You can omit name and description in following entries.





7.8  Internal History
=====================


  Z80EMU (only a Z80 with less CPC)
  ---------------------------------

  - v1.0 (1991)
    first version in Pascal (only Z80 emulation)
  - v1.2 (12.8.1992 - 16.8.1992)
    first version in C (translated with TPTC)
    Z80 problems: ADD HL..., DAA, LDIR set the P-flag incorrectly. BIT...
    set the Z-flag incorrectly, rotate instructions set the Z-flag and S-flag
    incorrectly; possible to use ROMs now.
  - v1.3 (18.8.1992)
    wrong port addressing: low byte incorrect. New memory management with
    128 KB RAM, 32 KB ROM
  - v2.0 (18.8.1992 - 22.8.1992)
    implemented COCPU technique to find errors (the COCPU uses separate
    memory and is only active in a special debugging mode). Z80 problems:
    AND... set H-flag incorrectly, CPI... set N-flag incorrectly. Formerly,
    the screen was only black and white, now it is blue and yellow as you
    know from a real CPC.
  - v2.1 (25.8.1992 - 27.8.1992)
    Emulation of all pens, colours in all modes. Writing only to the active
    screen which you can see. COCPU found an error: all instructions
    containing (IX+zz) with a negative distance were wrong ! Forgotten to
    take "signed char".
  - v2.2 (30.8.1992 - 3.9.1992)
    New keyboard routine, set palette without flickering (waiting for HSYNC).
    "Need-ROM" with COPYMATE introduced.
  - v2.3 (15.9.1992 - 19.9.1992)
    FDC emulation for sector load/save. COCPU found an error: LD XH,... was
    LD H,...
  - v2.3b (19.9.1992)
    Do screen update only if the screen is on RAM blocks 0..3 (and not 4..7);
    Made port FCxx an alias for FBxx (for CP/M Plus). At that time, I did not
    know that OUTI... predecrement the B-register.
  - v2.4 test (25.10.1992)
    Only R-register emulation if desired (per "DEFINE"); Now screen update
    every nth interrupt and not for every single byte written in memory.
    (Still very slow, because all is done in C). New memory management with
    blocks aligned to segments.
  - v2.5 test (31.10.1992)
    Changed memory management. Hardware scrolling and different screen sizes
    possible.
  - v2.6 test (5.11.1992)
    New keyboard handler from Arnt Gulbrandsen: all key combinations
    possible. Screen update in assembler.
  - v2.7 test
    Unsuccessfully tried to include the fast Z80 emulation from Juergen
    Weber.
  - v2.8
    Improved Screen update: Only changed parts are modified on the screen.
  - v2.9
    Using PC Timer to generate interrupts with 300 Hertz. Fast emulation runs
    only, if no ROM (banking) is needed.

  CPCEMU (now a CPC)
  ------------------
  - v0.2 (23.12.1992), following Z80EMU v2.9
    After nearly 4 hours analyzing with the Turbo Debugger I have found the
    error hanging the fast emulation: PUSH ES instead of PUSH DS.
  - v0.3 (28.12.1992 - 29.12.1992)
    Set N-flag for INI,OUTI. CPI in fast Z80 set wrong flags. RL (HL) used
    read segment (in DS) instead of write segment (in ES). LD A,R now
    produces random-numbers; All Tape routines implemented (but wrong
    CASSETTE IN CHAR).
  - v0.4 (1.1.1993)
    IN A,(n): A to b8..b15 (instead of B); RAM configuration 0xC3: corrected
    to 0,3,2,7 (for CP/M Plus). KC-Compact (a CPC compatible from former DDR)
    uses port EE00 - EE3D, but for what?
  - v0.5 (28.1.1993 - 8.2.1993)
    INIR,... R-register-incrementation depends on B, not on BC. CASSETTE IN
    CHAR corrected (wrong patch for CPC 6128).
  - v0.6 (23.3.1993 - 24.5.1993)
    Someone mentioned that the OUTI-instructions predecrement the B-register!
    Compiling the C parts in 386 code (with Borland C++ v3.1). Disk images
    have the suffix .DSK. CPCREAD.PAS corrected (head not initialized with 0)
    and translated to CPCREAD.C. Port addressing of the PIO improved (the CPU
    can read, even if the port is programmed for output, ...)
  - v0.7 (26.7.1993 - 29.8.1993) (unreleased)
    Totally new source, modularized, ...  Configuration file, more ROMs
    possible. Changed company name from 'Schneider' to 'Amstrad'. (You can
    choose between several names.)  RAM banking error removed. New
    documentation in German.
  - v0.8 (30.8.1993 - 9.9.1993)
    Slow emulation: parity instructions improved by using a table not only
    for parity. Z80: ED xx with illegal xx is ignored. New documentation in
    English.
  - v0.8a (10.9.1993 - 15.9.1993)
    Fatal error in fast emulation: If an DD CB xx instruction is executed and
    an interrupt occurs, the instruction is ignored!
  - v0.8b (16.9.1993 - 21.9.1993)
    Implemented a "real" VSYNC, if VSYNC_CT = 0. Corrected PIO port A
    problem: OUT &F400,xx with Port A in input mode was ignored. New joystick
    routine from Martin Zacho.
  - v0.8c (22.9.1993 - 13.12.1993)
    Checked documentation with "ispell". Emulation did not start, if
    "USE_JOYSTICK=1" and a joystick was not present (PUSH AX at wrong
    position). Slow Emulation: DAA corrected (brackets were missing since
    v0.8). Wrong patch for CPC 664 in interrupt routine. This patch replaced
    EI with NOP do avoid the problem with EI (enable interrupts one
    instruction later). Now correct for all CPCs.
  - v0.8d (14.12.1993 - 29.12.1993)
    FDC emulation rewritten for double sided formats. CPCTRANS replaces the
    old CPCREAD and allows you to read Vortex-disks after you have installed
    the patch 720KB.COM. Beside that, you can write disk images back to disk.
    New fileselect when pressing F3. Some port address aliases introduced,
    e.g. &7000 - &7f00 to address the gate array, &0c00,&1c00,&2c00,&3c00,
    &bc00 for the CRTC. Emulation of the R-register enabled.
  - v0.9 alpha (30.12.1993 - 20.1.1994)
    EMS memory possible with a special EMS/UMB-configuration. Binary digits
    in the configuration file. RAM-banking addressing corrected: emulator
    accepted &d0-&ff as &c0-&c7. Now up to 576 KB RAM with EMS.
  - v0.9b (21.1.1994 - 31.1.1994)
    Usage of EMS simplified by extended EMS (or LIM EMS 4.0) with more than
    4 physical EMS pages. File-select added to 'l' (debug menu), RUN" .
  - v0.9c (1.2.1994 - 29.4.1994)
    Some awful PC speaker sound (disable it with F4). File select also with
    'v'; this English documentation corrected; Soundblaster sound (can be
    improved); new CPCTRANS with command line parameters, direct FDC access;
    parallel adapter tested and the software improved. Fast Z80: INC (HL),
    DEC (HL), INC (IX+n), DEC (IX+n) for RAM below ROM corrected. PgUp,PgDn
    move oversized screens; parts of overscan screens are displayed.
    Now possible: 64K snapshots.
  - v0.9d (30.4.1994 - 12.5.1994)
    Interrupts during DI are not forgotten, and they are not enabled directly
    after an EI instruction any more. New color functions: now without snow
    under OS/2. Fast Z80: speed up code fetch.

  - v1.0 (13.5.1994 - 20.5.1994)
    Improved screen part: different character sizes from 1 to 8. File select
    added to SAVE" , added fast select by pressing a letter. Improved
    CPCTRANS with a verify option. A new setup menu, if you press F7. So you
    can disable colour flickering.

  - v1.0a (21.5.1994 - 9.6.1994)
    Improved setup menu with direct input or cursor keys, added German
    keyboard layout, added simple delay option. Correct display of smaller
    screen sizes (without parts of the bigger ones). Improved fast Z80 part:
    faster RRA,RLA, ... faster CB xx instructions. Added more illegal
    instructions (ED xx). LD D,XH and LD YL,YH were missing ! Corrected CPDR,
    CPIR with BC=0 (0 means 65536 on a Z80, but it is 0 for the 80x86 REPE
    prefix!). DAA flags corrected. New software for the parallel adapter:
    Now it is possible to send to the CPC. Thanks to Bernd Schmidt for
    pointing out that an interrupt increments the R-register by 1. With his
    help, the PIO port C register emulation has been improved.

  - v1.1a (10.6.1994 - )
    A new era of CPCEMU has arisen: Amstrad has allowed the use of the ROMs!
    Changing in the configuration file: ROM_BLOCKS -> ROM_BLOCK, DISC_BYPASS
    -> DISABLE_ADOS, no space separating '=' needed, Changings in sound part,
    graphics part: vertical size by VGA-CRTC. Joystick calibration is in the
    setup menu now, tape routines for saving are improved. FDC part improved:
    now you can use COPYMATE. Insert non-data format disks without read error
    (without a seek to track 0). Another delay in CPCTRANS, I hope, you will
    not need the turbo switch any more; formatting of disk images. Corrected
    PIO port C another time: it is cleared after out &7f00,n. Major changes
    in the configuration file: Now with conditional configuration (#IFCPC,
    #ENDIF). Some tokens changed (VSYNC_CT -> /, DISC_PATH -> /, SNAP_PATH ->
    SNAPSHOT, DRV_A -> DRIVE_A, DRV_B -> DRIVE_B). Load programs from inside
    ZIP archives. You will need PKUNZIP.

  - v1.1b (17.8.1994 - 2.9.1994)
    Multimodes introduced, that means different screen modes on the same
    screen. The screen update is partitioned in up to 6 areas, each one is
    updated when an interrupt occurs. (Can be improved.) Possible now: 128K
    Snapshots, extended for multimodes. CPCPARA improved: Now you can
    transfer binary files with header. CPC 6128 Plus detection included.
    More port aliases included.

  - v1.2 (3.9.1994 - )
    This version was released. Mainly there are some changes with
    the help menu.

  - v1.2a (27.9.1994 - )        (was available as UPD12A.ZIP)
    File Select: Only the available drives are displayed.
    And: With the driver ANSI.SYS the background of some text was black.
    TMP_PATH: You can specify a drive without path.
    DOS Shell (F7): CPCEMU is swapped to XMS, EMS or disk first, so you
    have much memory in the DOS shell. (This feature is taken from the
    Public Domain Program SWAP300.ZIP by Marty Del Vecchio.)
    Screen update could be corrupted, if the screen width was not
    divisible by 4.
    Another CPCEMU version to get even more speed: C2.EXE. It uses a
    different memory management with two EMS frames with 64KB each.
    One for reading and one for writing. But it runs only with EMS.
    The ROMs are also (c) by Locomotive Software, not only Amstrad.

  - v1.2b (  )
    There was no stereo sound on a Soundblaster Pro even if the
    configuration said so. If no Soundblaster was found there was no
    sound at all until you use USE_SB=0.
    Fast-Z80: Changed some word accesses to byte accesses. That's a bit
    slower but does not crash the computer every time you do a word
    access at address 0xffff.
    Fast-Z80: Problem with EI HALT DI corrected: The address to HALT was
    pushed instead that one of DI.
    corrected English documentation
    improved CPCPARA and PCPARA v1.1: adapter test, much more speed CPC->PC:
    approx. 1600 bytes per second reading from disk! (486/66), statistics.
    So you can transfer 16KB in 10 seconds! Thanks to Klaus Weber for
    pointing out, that it was much too slow.
    In PCPARA there was a DELAY(1) after every nibble to wait a millisecond.
    This is not necessary.

  - v1.2c (28.2.1995 - )        (was available as UPD12C.ZIP)
    Parts of CPCEMU rewritten in C++. This allows inline functions and
    improved interfaces to keep a better overview over the project.

  - v1.2d (16.3.1995 - )        (only for mailing list 'subscribers')
    Fast-Z80: Internal changes not visible to the user, except a little
    speed improvement. All data is kept in the data segment now instead
    of the code segment.
    Finally introduced the absolutely necessary mode for fast computers:
    'realtime CPC' (Selectable from the setup menu or REALTIME=1).

  - v1.3 (16.4.1995 - )
    Poke database for easy poking, French documentation, FDC format
    command (re-format disk images of the same size),
    new menu system with mouse support (MOUSE=1),
    insert disk images with read-only DOS attribute (insert them as read
    only), debug menu: 'find' added

  - v1.3a (30.4.1995 - )        (was available as UPD13A.ZIP)
    With version v1.3 Boulder Dash did not run, even if it did with v1.2.
    The interrupt mode 2 of the Z80 was not simulated correctly
    (PUSH/POP forgotten). The slow Z80 emulation had a similar bug.
    CPCTRANS: Option -f 6 enabled.

  - v1.3b (20.5.1995 - )        (is available as UPD13B.ZIP)
    Some users mentioned that there was no Soundblaster sound output since
    version 1.3.

  - v1.4 (v1.3c)
    GUS sound support by Ulrich Doewich; online help in English, German,
    French and Spanish; complete French documentation;
    support for 2 joysticks; VESA videomodes for higher resolutions;
    improves setup menu and configuration file; load and save
    configurations added to the setup menu; improved FDC routines for
    non-standard formats; Extended disk format;
    user-configurable colours and keys;
    improved CPCTRANS (v2.3); new SNA2GIF (v1.1);
    fast Z80 emulation: sometimes the screen was not completely cleared
    after a reset (problem with HALT);



  CPCEMU is written in C++ and assembler, using Borland C 3.1 with 386
  optimization and Turbo Assembler. For Debugging the Turbo Debugger
  was used.
  The colours were composed with the program VGAMETER by J. Stephen
  Shattuck, Jr., with the CPC connected to a TV by a Scart adapter.



------------------------------------------------------------------------



(From this point you can continue reading without danger.)



Appendix
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A.1  Glossary
ððððððððððððð

Here some computer terms are explained. I do not claim to give complete
or precise definitions. The terms are described with the view to the CPC.
References are marked with "¯".


386/33 (AT 386/33)
  Short term for ¯PC AT with 80386 processor, clocked with 33 MHz.
  Because of the "high" clock rate it should be a 386DX with a real 32
  bit data bus, not the cheap 386SX with a 16 bit data bus.

AMSDOS (Amstrad DOS)
  ¯DOS developed by ¯Amstrad, for the ¯CPC computers.

Amstrad
  British computer manufacturer, who has designed the ¯CPCs.

Archive
  Storage of files.
  Or: One file, including several other.
  In ¯ZIP archives the files are compressed before including them.

ASCII (Abbreviation for: American Standard Code of Information Interchange)
  On a computer all characters, numerals are represented internal as numbers.
  Most computers use ASCII, with the letter "A" coded as 65. ¯PC and ¯CPC
  also use ASCII. In ¯Locomotive-BASIC you can save an ASCII file by typing
  'SAVE"<filename>",A'.

Basis Address
  This you have to specify in many ¯setups if you own a soundcard.
  CPCEMU looks for an ¯environment variable.

BASIC (Abbreviation for: beginners all purpose symbolic instruction code)
  Widely used, easy to learn programming language for home- and personal
  computers. Former every computer had had his own BASIC dialect.
  Modern BASIC allows structured programming, so you are not forced to
  program "spaghetti code" any more.
  Also the ¯CPC has its own BASIC, the Locomotive BASIC by a company of
  the same name.

Batch File
  Contains instructions you normally type in your computer. If you call
  such a file, the instructions are executed one by one, even if you input
  them.

BASIC File
  See ¯File.

BBS

Binary File
  See ¯File.

BLASTER environment variable
  See ¯environment variable.

C64:
  Home computer by the company Commodore with 64 KB ¯RAM, very popular.
  Because of the huge software supply it was "the game computer" for many
  years. Later it was pushed aside from the Commodore AMIGA, but despite
  its old technique it survived longer.

Clock frequency
  Clock the processor is connected to. It determines the speed of the
  processor in a significant way. Today's 486DX2/66 processors are clocked
  internally with 66 MHz.
  The Z80A in the ¯CPC is clocked with 4 MHz, running actually with 3.3 MHz
  because he has to wait periodically for the screen update.

Command line parameter
  Parameter you give in the command line after the file you want to call.

Configuration
  Here: Configure a program for his own needs.
  You can do that with the ¯Setup or a configuration file.

CPC (Abbreviation for: Colour Personal Computer)
  Developed by the company ¯Amstrad, was available in different types.
  Please read the introduction again.

CPC printer port
  Centronics interface of the ¯CPC to connect a printer.
  Unfortunately the CPC designers were too economic: It has only 7 bits.
  With a short wire it was possible to extend it to 8. For this the
  cassette port was "misused", not needed when printing.

CPC firmware manual
  A book about the ¯CPC, especially describing the operating system
  interface of the CPC.

CPC newsgroup
  A newsgroup only for the ¯CPC. It is called "comp.os.amstrad.8bit"
  and was created in august 1994.

CP/M Plus (Abbreviation for: control program for microcomputers)
  Operating system from the company Digital Research, mainly for 8 bit
  microcomputers. Widely used until IBM decided to use MS-DOS for its PCs.
  CP/M Plus (CP/M 3.0) was the successor of CP/M 2.2 and was included
  in the software package of the ¯CPC 6128.

CTRL/SHIFT/ESC (control/shift/escape)
  "Three finger combination" on a ¯CPC to cause a reset. It is similar to
  the reset combination 'CTRL/ALT/Del' on a PC. Some programs block
  such a reset so you have to turn off the computer or use the reset
  button. The CPCs had no button, but it was easy to build one.
  In CPCEMU the function key F8 is the reset button.

Cursor
  Character on the screen which shows you the current writing position.
  Somewhere on the keyboard there are cursor keys to move the cursor
  around.

D-Sub
  Connectors with a special form.

Dk'tronics
  British company offered hardware extensions for the ¯CPC, e.g.
  memory extensions.

DMA (Abbreviation for: Direct Memory Access)
  Direct access to the computer memory without using the processor.
  Used with disk drives, but to be cheap not implemented in CPCs.
  The Soundblaster card can also use a DMA channel, getting digital
  sound data "through" it.

DOS (Abbreviation for: disk operating system)
  Disk oriented operating system, e.g. AMSDOS, DRDOS, MS-DOS.
  Today it is a synonym for MS-DOS.

DOS Search Path
  DOS uses a path along subdirectories to find a file.
  It is set with the environment variable 'PATH'.

DRDOS
  MS-DOS compatible ¯DOS by the company Digital Research.

E-Mail (Abbreviation for: Electronic Mail)
  Using a computer as mail-box.

EMM (Abbreviation for: Expanded Memory Manager)
  Similar to ¯EMS.

EMS (Abbreviation for: Expanded Memory System)
  Memory extension for the ¯PC, to get around the 640KB memory limit.
  With the banking technique other memory pages are mapped in an EMS
  window. EMS was developed by Lotus, Intel and Microsoft, thus it is
  called LIM-EMS.
  There is hardware-, emulated and simulated EMS.
  Special memory cards supply hardware EMS, mainly used on old PC XTs.
  On a PC AT with at least a 80386 processor it is possible to have
  emulated EMS by using the paging mechanism for banking.
  This sort is supplied by EMM386.EXE and should used to speed up CPCEMU.
  Simulated EMS is too slow, it has to copy the memory pages.

Emulate
  Imitate a system (hard- or software) by another one.
  The imitating system computes the same results on the same data as
  the imitated system.
  CPCEMU emulates a ¯CPC on a ¯PC.

Emulator
  The system ¯emulating another one.

File
  Collection of data belonging together. On the ¯CPC there are files of
  different types, e.g BASIC files with BASIC programs usually having the
  extension '.BAS', ASCII files with any text, and binary files with any
  bytes, usually having the extension '.BIN'.
  Binary files can contain machine programs or other data.

Format definitions
  Definitions of disk formats.

FTP (Abbreviation for: File Transfer Protocol)
  A protocol to transfer files in computer networks.
  Also, the program running this protocol is called "FTP".

Hardware
  Parts of a computer you can "touch", e.g. periphery like printer,
  monitor; internal it is the processor and other ¯hardware chips.

Hardware chips
  Components inside the computer, e.g. processor, memory chips, floppy
  disk controller, ...
  Inside the CPC there are the Z80 processor, the Gate Array, the CRTC
  6845 for addressing the screen memory, the PIO 8255 for input/output,
  the sound chip PSG AY 3-8912, the floppy disk controller FDC 765, ...

Hardware scrolling
  Moving the screen without having the processor to copy from one part
  to another. The processor has to modify only the screen base address,
  the rest is done by a hardware chip.

Initialize
  Fill the memory with special values, so variables are defined.

Interface
  Connection of a computer to its periphery or from one program to another.
  Thus there are hard- and software interfaces.
  The so-called Centronics interface is a parallel interface, transmitting
  the bits of a byte parallel. With serial interfaces it is necessary to
  transfer the bits one after another.

Internet
  An Internet is composed of several sub-networks of computers.
  Here: *The* Internet, a worldwide computer network for communication.

Interrupt
  If the processor gets a signal with higher priority, it interrupts
  the running program and calls a special interrupt handler. When
  finished it continues with the interrupted program. On a PC there
  are different interrupt signals, e.g. when you press a key, when a
  timer runs off, when data from the serial interface has arrived
  (e.g. when you move the mouse), when the soundcard just played its
  last sample and needs more data, ...
  The Z80 in the CPC is interrupted 300 times a second.

Interrupt number IRQ (IRQ=Abbreviation for: Interrupt Request)
  On a PC, different ¯interrupts have different numbers.
  For example, the keyboard interrupt has number 9, the timer interrupt
  has number 8. If you press a key, the keyboard sends an interrupt
  request to the processor, so it is informed.

Jumper box
  An adapter box to realize any connection between two connectors by
  using short wires which must be soldered.
  See also ¯Wiring Box.

Keyboard handler
  A program called when the keyboard generates an ¯interrupt. The handler
  gets the number of the key which is pressed or released.

LIM standard (Abbreviation for: Lotus Intel Microsoft)
  Memory expansion (¯EMS), developed by Lotus, Intel and Microsoft.

Locomotive
  British company which wrote the ¯BASIC of the ¯CPCs.

Mailing list
  A service from me, for which I add your email address to a list.
  So you will be informed about news concerning CPCEMU.

Microchannel
  Special bus architecture.

MS-DOS (Abbreviation for: Microsoft Disk Operating System)
  Operating system, developed by the company Microsoft for 16 bit
  processors (8086). The most popular operating system for the PC.
  Still in use on the 32 bit processors 80386 and 80486.

Multi Modes
  Programming technique to have different screen modes simultaneously
  on the screen. The screen mode is changed during a screen refresh more
  than one time. On the CPC you get zones with high resolution, few
  colours and low resolution, many colours.

Multiface II (Abbreviation for: Multipurpose Interface)
  A hardware extension for the CPC. Allows to interrupt any program at any
  time to analyze or save it.
  Developed by the British company Romantic Robot.

Number representations
  Depending on the selected base, there are different representations
  for the same number.
  Well known is the decimal representation with basis 10 and digits 0 to 9.
  Computers use the binary representation (base 2) with digits 0 and 1.
  Programmers like the hexadecimal representation with base 16, because
  16 is a power of 2 (2 powered with 4). Then the representations can
  be easily computed into each other. Besides a byte needs only 2 digits
  (0 to 9, A to F) in the hexadecimal notation.

OS (Abbreviation for: Operating System)
  A program needed to use the computer. It provides basic functions to
  application software. New operating systems do complicated tasks like
  program scheduling in multitasking systems, ...

OS/2 DOS box
  A window under the 32 bit operating system OS/2 by IBM, where you
  can run DOS programs. The so-called DOS compatibility box.

Overscan
  The border surrounding the writable area on the screen.
  On a PC it is very small but you can change its colour, e.g. in CPCEMU
  with 'BORDER 10'. On the CPC the overscan is much wider, so
  programmers have looked for possibilities to write to it. With a
  programming trick it is possible to write to the whole screen.
  This programming technique is called overscan.

Parameter
  Variable with a fixed meaning, the behaviour of the program relies on it.

PC (Abbreviation for: Personal Computer)
  Computer with a microprocessor as processor (or CPU=central processing
  unit). Today a synonym for the IBM PC with 8086 or 8088 processor.
  PC AT (advanced technology) are computers with a 80286, 80386 or 80486
  processor.

PEEKs and POKEs:
  ¯BASIC instructions to modify the memory directly.
  'PEEK(<address>)' is used to read a byte from memory,
  'POKE <address>,<number>' modifies the memory. Programs with many PEEKs
  and POKEs are hard to understand, but sometimes it is necessary to
  break through the limits of BASIC, especially if the BASIC only has few
  instructions.

PKUNZIP
  Program by PK-Software to decompress ¯ZIP files.

RAM (Abbreviation for: Random Access Memory).
  Memory chip. Memory of the computer.
  The CPCs have 64KB RAM (kilo bytes) or 128KB. With hardware extensions
  they could have up to 576KB RAM.

ROM (Abbreviation for: read-only-memory).
  Memory chip. Memory that can only be read but not changed.
  It is available directly after switching on the computer.
  The CPCs have 16KB ROM ¯OS, 16KB ROM ¯BASIC and 16KB ROM for the AMSDOS.

ROM Image
  File with the contents of a ¯ROM. If you read out a ROM and write the
  bytes into a file you will get a ROM image.

RS-232
  Serial Interface to connect monitors or printers to the computer.
  (RS 232 C).

Schneider
  German company, which sold the CPCs in Germany.

Screen mode

Setup
  Changing ¯parameters of a program, so it behaves differently.
  You can tell the setup, that you have a soundcard, that you want to use
  a joystick, ...

SIMTEL
  A big software archive in the USA.
  The SimTel Software Repository is maintained by Coast to Coast
  Telecommunications, Inc. (CCT) on its host computer on the Internet
  located at "SimTel.Coast.NET". This archieve is mirrored (copied)
  to other sides.  One mirror site is Oakland University located at
  "OAK.Oakland.Edu".

Snapshots
  A memory dump completed by internal states of the ¯hardware chips.
  It contains a complete momentary state description of the computer.
  If the snapshot is reloaded, the computer is set back to the state
  described in the snapshot.
  Thus it is similar to a real snapshot, only inside the computer.

Software
  Programs of a computer system.

Soundblaster
  Soundcard of the company Creative Labs.

Spectrum
  The Sinclair Spectrum is a home computer developed by the company Sinclair.

Turbo Pascal compiler
  Pascal is a higher programming language which allows structured
  programming, today used in many schools.
  If one talks about Pascal, he means mostly Turbo Pascal, even if this
  is only an extended Pascal by the company Borland. The Turbo Pascal
  compiler is particular fast because it compiles the program in one pass.

Utility
  Useful program.

VGA (Abbreviation for: Video Graphics Array)
  Graphics standard on the PC. Successor of CGA (Colour Graphics
  Adapter), MCGA (Multi Colour Graphics Adapter) and EGA (Enhanced
  Graphics Adapter). Extended to SVGA (Super VGA) with higher resolution.

VGA-BIOS (Abbreviation for: VGA Basic Input Output Operating System)
  The operation system for the ¯VGA graphics card.

Windows
  Something you can put on ¯DOS.

Wiring box
  A adapter to realize any connection between two connectors by using
  short wires. In comparison to the ¯jumper box, the wires need not be
  soldered.

Z80
  An 8 bit processor developed by the company Zilog. It is upwards
  compatible to Intel's 8080 and was very popular.
  In the ¯CPC there is the Z80A which is clocked with 4 MHz.

Z80 instructions
  Machine instructions which the ¯Z80 understands.
  They are only number columns, so to remember them more easily mnemonics
  were introduced, which are translated by an assembler into binary code.
  The instruction "LD A,B" loads register A with the contents of register B
  and is the same as the binary code 0x78.


ZIP
  A special process to compress files.
  The ¯archives have the extension "ZIP".





A.2  Bibliography
ððððððððððððððððð


The CPC manual is indispensable for CPC beginners:
- Spital Ivor und Perry, Roland und Poel, William und Lawson,Cliff:
    CPC 6128 Benutzerhandbuch, Schneider Computer Division 1985,
    Originalausgabe (c) 1985 (my one contains 1895)
    by AMSOFT, AMSTRAD Consumer Electronics plc and Locomotive
    Software Ltd.

An excellent commented ROM listing, with starting chapters dealing
especially with the software side of the CPC:
- Janneck, Joern W. und Mossakowski,Till: ROM-Listing CPC 464/664/6128,
    Markt & Technik Verlag 1986

On the contrary: unfriendly composed, rarely commented, dealing more with
the hardware side:
- Brueckmann, Englisch, Gertis: CPC 464 Intern mit kommentiertem
    ROM-Listing, Data Becker 1985

Good to learn C, with many exercises:
- Kellay, Al and Pohl, Ira: A Book on C, Second Edition, 1990 by
    Benjamin/Cummings Publishing Company, Inc.

The C++ standard book:
- Stroustrup, Bjarne: The C++ Programming Language, Second Edition,
  Addison-Wesley, 1992

Another nice C++ book:
- Eckel, Bruce: C++ Inside & Out, 1993 by Osborne McGraw-Hill

Hints, how to write an understandable and good manual, gives:
- Boedicker, Dagmar: Handbuch-Knigge, Software Handbuecher schreiben
    und beurteilen. Wissenschaftsverlag 1990





A.3  Index
ðððððððððð

The numbers behind the entries show you the chapter where they are described.

(not complete)

#ENDIF 4.2
#IFCPC 4.2
22DISK 5.1.2
Adapter, parallel 5.2
AMSDOS_DI 4.2
AMSDOS_SPDUP 4.2
BLASTER Environment 2.3.2
BREAK_MASK 4.2
Cassette 3.2.2
COLOUR 4.2
Configuration file 4.2
CPC 1.3
CPC Newsgroup 6.2
CPCEMU.CFG 4.2
CPCPARA.BAS 5.2
CPCREC.BAS 5.2
CPCTRANS.EXE 5.1.1
Debug Menu 7.3
DELAY  4.2
Disk 3.2.1
Disk Image 3.2.1
DRIVE_A 4.2
DRIVE_B 4.2
EMS_EI 4.2
EMS Memory 2.3.1
Function key 3.1
INT_FREQ 4.2
INT_RESUME 4.2
JOY_CALIBRATE 4.2
KBD_LANGUAGE 4.2
Keyboard 3.1
Menus 3.2.1
Multi Mode 4.1
MULTIMODE 4.2
PCPARA.EXE 5.2
PIO_PORT_B 4.2
PRINTER 4.2
RAM_SIZE 4.2
ROM_BLOCK 4.2
ROM_PATH 4.2
SBLASTER 4.2
SB_DELAY 4.2
Setup menu 4.1
SHOW_CONFIG 4.2
SNAPSHOT 4.2
Snapshot 3.2.3
SOUND 4.2
Soundblaster 2.3.2
TAPE_BYPASS 4.2
TAPE_PATH 4.2
TMP_PATH 4.2
VSYNC Bit 4.1


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