Re: VC-20 all 16 colours full-screen?

From: silverdr_at_wfmh.org.pl
Date: Thu, 2 Sep 2021 12:49:56 +0200
Message-Id: <844F8AC8-4722-4BCA-BB11-EB3ABA238C46_at_wfmh.org.pl>
> On 2021-09-02, at 09:49, Anders Carlsson <anders.carlsson_at_sfks.se> wrote:
> 
> silverdr wrote:
> 
> > When I run it on `xvic` I still get one "column" worth of border colour on both left and right.
> 
> I just tested on a real PAL VIC-20. With POKE 36864,0 and POKE 36866,31 (+128 depending on the location of the screen matrix) you eliminate the border so you can adapt Michiel's program with these changes. Combined with POKE 36865,0 and POKE 36867,39 (or even 41 if you really must ensure that the entire screen is covered), it should be possible to cover the ENTIRE screen area. Since you're not putting any text or graphics on the screen, we can ignore the fact that quite a bit of the screen will fall outside of visible area on pretty much every monitor you can find.

Yes - it's about video signal, not how this or that monitor/TV is going to display it. On my displays I can see the whole frame as every studio monitor has "underscan" function meant for monitoring parts, which are not normally visible.

> Sure perhaps you can capture the video signal with some device that still picks up border, but since we set VIC-I to begin the screen at the absolute lowest X and Y coordinates and expanded the screen the maximum number of columns and rows (with 8x16 mode), if it still displays border colour at any place, there is nothing we can do about it from software.


10 poke 52,28
20 poke 56,28
30 clr
40 poke 36864,2
50 poke 36865,5
60 poke 36866,32
70 poke 36867,39
80 poke 36869,255
100 fori=7168to i+570
110 poke i,.
120 next
130 c=0
135 poke36879,c*16+11
140 get a$
150 if a$="" then 140
170 c=c+1
180 if c>15 then 130
190 goto 135

seems to do the trick on the emulator - there is no border colour anywhere except the last one or two lines. That's all I need if it behaves the same on the real hardware.

Now time to get a working VC-20. What's the most common "black screen" suspect on the VIC?

-- 
SD! 
Received on 2021-09-02 13:00:02

Archive generated by hypermail 2.3.0.