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 A further extensions of the UBERMODE-graphics-mode from 2013 now
 providing a resolution of 224x283 pixels on a PAL VIC-20 with added
 raster-splits for more color-choices per picture:
 
 - 224x283 hires or 112x283 multicolor pixels (true resolution)
 - 8x8 blocks for foreground color (4x8 for multicolor)
 - background/border color split every 8 rasterlines (36 total)
 - auxiliary color split every 32 lines (9 total)
 - 24K RAM expansion required
 

 Short reference:
 ----------------
 
 GRAPHIC ON:                  SYS 9774 (SPACE to return to BASIC prompt)

 See pgm-import on how to set single pixels, clear the screen and on how
 to set the color-RAM and backgroud/border/auxiliary colors.
                              
 
 Technical background of the graphics-mode:
 ------------------------------------------

 Back in 2015, a short time after creating some different modes for the
 VIC-20 I realized I was lying about 224x280 being the maximum possible
 resolution on the PAL VIC-20. In fact 3 more lines are possible and
 visible in VICE as well as monitors that can adjust the viewable area
 as much as possible, such as the Commodore 1084. With this monitor I
 checked that in fact 224x283 would be the maximum resoltion fully
 visible. I tried expanding it to 232 horizontal width. but this would
 lead to some pixel being no longer inside the visible area.

 As soon as I had the 224x283-mode working I still had some raster-time
 left which I used for raster-splits of the remaining global colors as
 much as possible.

 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 17

 in the Programming-subforum.

 This mode leaves just 2 cycles of CPU-time per raster unused -
 a single NOP-operation.

 As usual a picture converter for converting monochrome 224x283 pixel
 .pgm-files is included in this package as well. This relatively short
 program also shows how to set pixels and colors. Simply convert any
 picture with a 4:3 aspect ratio without ratio correction to 224x283 on
 your PC and then have the PGM-converter run through it. This will
 create an executable files which can be RUNed or started by SYS 9774.

 With this mode the PAL VIC-20 can now display 63392 pixels, just 608
 short of the C64 in hires-mode! If you have questions, problems or
 suggestions or just want to comment, feel free to do so in the forum or
 just email me.

 tokra, signing off, July 19th 2019

 Contact: tokra@tokra.de
