LikTwiik v1.7á;

Videomodes up to your ears!



50, 60, 70hz... what's the difference, except flicker?

70hz is the highest normal VGA refresh rate, used by the 350 and 400 line
modes. 60hz is the refresh rate used by 480 line modes and NTSC tv's (usa).
50hz is the refresh rate used by PAL tv's and video's.


--- Why use 50hz? ---

50hz indeed flickers a little, but that is almost invisible for moving
effects.

 þ MUCH more rastertime per frame

 þ Faster graphics memory! (the gfx processor doesn't have to access its
   memory so much, so you can instead =)

 þ PAL-compatible! If you happen to own a vga-2-tv converter (like me) then
   you don't need any stupid driver whatsoever if you use 50hz!


About the mode files:

The mode files are in pure basic. The easiest way to try them is to load
them into QBASIC, type SCREEN 13 at the top, and run with SHIFT-F5.
Translating them to assembler/c/pascal should be a really easy task, but
that's the price you have to pay for not coding basic like me (hehe)... no
i don't code qbasic, but powerbasic with inline assembler. nevermind, that's
another story.

i had severe problems with changing the 3C0 port, so you must set a 256 or
16 colour graphicsmode first (depending on which mode file you want to use).
For textmodes, just set a textmode. =)


Filenaming system:

70\320200c.256      is 70hz, 320*200 and chained. If this file exists then it's
                    pure mode 13.
                    The C means CHAINED.

50\320200c.256      is the mode 13 equivalent in 50hz. Mind you that it is PAL
                    standard, i.e. 400 lines don't use the whole screen.
                    However, non-digital vga screens aren't aware of this fact,
                    so it displays them fullscreen anyway.

50\320200co.256     is a mode 13 like mode in 50hz, but this one uses
                    600 lines instead of 400 -> it's fullscreen, and even
                    overscan. (that's what the O is for). However, on old
                    vga screens, this mode is MUCH too big for the screen
                    (in Y-axis). Therefore, i recommend you to do an
                    interactive mode selection in beginning of the demo.

50\256192c?.256     Now THIS is an interesting mode. This mode is made by me
                    from scratch, and nobody has made anything similar before.
                    What's so special about it?

                    þ 256 pixels width (though this is not unique)
                    þ fullscreen! (now THAT is unique!)
                    þ SQUARE PIXELS! (even more unique for a 256 width mode!)

                    However, this is a fussy mode. I have made 11 (yes ELEVEN)
                    different versions of it, to make it work on all
                    screens. i haven't found a screen it doesn't work on!
                    (except for old crappy SALORA's which can't even handle
                     320*200 60hz.)

                    mode 1-B are different fullscreen versions, and the
                    unnumbered one is a non-fullscreen version, but that one
                    is (should be) compatible with ALL equipment (yes it
                    works on my little sisters b/w vga monitor, and also
                    with my vga-2-tv converter).
                    
                    Anyway, all nine modes are all the same TO THE PROGRAMMER,
                    but NOT to the display equipment! Therefore, if you wish to
                    use this mode, you *MUST* make a mode selection setup, in
                    which you should be able to test the modes. I have made a
                    sample mode selector which you can try.

                    If you can't get ANY of the fullscren version to work on
                    your screen, then there is a way for you to define your
                    own! Jump into VMSELECT and read the on-screen
                    instructions! Then you can (hopefully) make a mode that
                    works on your screen, and send it to me, and i'll include
                    it to the forthcoming LikTwiik packets!

50\376564.256       This is an unchained mode (mode-x format, 4 planes).
                    The unchained modes are hell if you want to run effects,
                    but they are nice to show pictures etc.

50\200.256          This is not a real videomode, but more a STANDARD setting.
                    It only changes the vertical registers, so you can get
                    50hz in almost any 400 line mode (like 320*400, 640*400,
                    320*200 etc). What's the use? Well, if you want to use an
                    SVGA mode (like 320*200*65536 colours, or even 24 bit) then
                    just set the mode, and include this file! bang, there you
                    have your favourite refresh rate in your favourite SVGA
                    mode.


--- I have had lots of help by Robert Schmidt's TWEAK (thanks dude! =). ---

Message to him:     Tweak is some fine piece of code, but it has one bad
                    thing! It waits for vblank when you test the mode. This
                    is not so great, because if the mode is so bad that it
                    NEVER gets a vblank, all i can do is to push the reset
                    button. i had to debug tweak.exe to fix this =)...


--- Compatibility Credits ---

    These people have modified modes to get them to work on their screens
    (i.e. better compatibility!):

    Mr-Z (.hu)       : 256*192c9 - for Hyundai HCM-425e LR...
    Flux/Inside (.fi): 256*192c9 - for Panasonic PanaSync 5G, 17"

    Thanks dudes!


--- Other Credits ---

    Huge thankyou's to Shadow/Noice for making a fabolous converter in only
    4k!!! (no i couldn't redo that in basic =)


--- Productions which have used modes from Liktwiik so far: ---

    Xtal by Complex                                     (code: Jmagic)
    Shoebox Universe BBS intro                          (code: Naali)


well thats all i know of by know, but more is to come!



--- Last words ---

    If you use any of these modes, please credit me, and let me know too, so
    that i can add the production to the list below! =)
    
    And, if you want a certain mode, then let me know, and i'll see what i can
    do! i'm very friendly. (yes i really am =)



My addy:

Leif Claesson
Str”ms v„g 37
420 17 Olofstorp
Gothenburg, Sweden

+46-31-7020385

Samskolan@one.se

irc #coders


see you!


///Liket of Goto10

