Presenting 192i416 mode for VIC-20 NTSC only
--------------------------------------------

Another true interlace mode for the VIC-20
Nearly 25% more resolution than the C64 in
hires-mode

192x416 pixels hires = 79872 pixels!
 96x416 pixels multicolor
   8x16 color blocks

After finishing the MIFLI-mode which combined
high resolution with maximum color-flexibility,
I was looking for a new frontier: the maximum
possible hires-resolution on an NTSC-VIC-20.

It was clear interlace would have to be used
again. Finding the correct setup for this mode
proved very difficult and only when I gave up
after about a month and settled for a lower
resolution I finally had a breakthrough idea how
to implement 192x416 after all.

You can read more about the genesis of this mode
in the VIC-20 Denial forum at

http://www.sleepingelephant.com/denial/

Look for the thread

** New Frontiers in VIC-Hires-Graphics, Part 13

in the Programming-subforum.

This mode uses the VIC-20 CPU to the max - more
than any other mode I did before. Less than 1%
of processor-cycles remain unused per frame.
Most of these are needed to keep the mode
relatively easily adressable later on when
setting pixels. Also a 32K expansion is
required, since the display routine alone takes
up nearly the full lower RAM expansion of 24K,
leaving only 7K in BLK5 for BASIC-programs.

You will find a picture converter for converting
192x416 monochrome .pgm-files in this package as
well. This relatively short program also shows
how to set pixels. Also included is a text2pgm-
converter by Mike, adapted for a 48x52 text
screen like this one.

tokra signing off, July 20th 2012
