Search found 2883 matches

by Mike
Sat Nov 04, 2017 1:04 am
Forum: Hardware and Tech
Topic: 6561 Die Shot Reversing Explorations
Replies: 54
Views: 830

Re: 6561 Die Shot Reversing Explorations

What if we extended Kakemoms question to the other three colours? They all come from control registers. Has anyone tried changing those mid character? I'm guessing someone has. Has been done, yes, and works ... In the die shot, they look like they're read from the control registers on every pixel. ...
by Mike
Fri Nov 03, 2017 11:46 am
Forum: Hardware and Tech
Topic: 6561 Die Shot Reversing Explorations
Replies: 54
Views: 830

Re: 6561 Die Shot Reversing Explorations

I can't remember if its possible to change a character halfway through it, e.g. changing the color byte. Obviously the Character RAM won't be fetched twice as there is no time for it, but the color RAM could. Anyone knows (or has experimented) around this? I have experimented with this and don't th...
by Mike
Fri Nov 03, 2017 11:37 am
Forum: Programming
Topic: Load VIC-20 Tape Images
Replies: 13
Views: 1239

Re: Load VIC-20 Tape Images

Anyway, I read the other thread...typical Mike stuff. Just swat everyone's ideas down and say they aren't the best way, because it isn't your way. Then claim that posting about retro ideas in a retro forum is annoying. hahaha. In fact, there in that thread died, possibly, a cool idea in the making ...
by Mike
Thu Nov 02, 2017 9:44 am
Forum: Hardware and Tech
Topic: VIC-2000 Expander. Modern Power Using Retro Parts!
Replies: 114
Views: 2009

Re: VIC-2000 Expander. Modern Power Using Retro Parts!

Something like... "hey, did you know you can create a new yellow hue by sending 2 bits really fast at pixel location 112?" ... yeah, those kind of analog quirks will not be part of my new system, only digital quirks I can do in VGA. Don't worry. The VIC-I's pixel clock is a little bit too...
by Mike
Thu Nov 02, 2017 5:21 am
Forum: Programming
Topic: ?FORMULA TOO COMPLEX
Replies: 11
Views: 288

Re: ?FORMULA TOO COMPLEX

why a stack of only three strings deep? [...] What is the thought behind that? That setup is probably sufficient for most non-trivial string expressions. For example, even something like A$=LEFT$(LEFT$(A$,M-1)+LEFT$(B$,N)+MID$(A$,M+LEN(LEFT$(B$,N))),LEN(A$)) works and gives the same result as the l...
by Mike
Wed Nov 01, 2017 5:10 pm
Forum: Hardware and Tech
Topic: 6561 Die Shot Reversing Explorations
Replies: 54
Views: 830

Re: 6561 Die Shot Reversing Explorations

http://sleepingelephant.com/ipw-web/bulletin/bb/viewtopic.php?t=7629&start=39 :shock: This would explain why display starts again in the last displayed line when YPOS=0! That "last" line continues from the current text offset, but then the text offset must get reset to the start durin...
by Mike
Wed Nov 01, 2017 4:04 pm
Forum: Hardware and Tech
Topic: 6561 Die Shot Reversing Explorations
Replies: 54
Views: 830

Re: 6561 Die Shot Reversing Explorations

I recall it being mentioned in the forums here in years gone by that the visual artefact observed in the border area immediately before the first column was the VIC chip fetching the data required for the first column, caused by some sort of interference within the chip. Am I remembering correctly?...
by Mike
Wed Nov 01, 2017 11:46 am
Forum: Hardware and Tech
Topic: VIC-2000 Expander. Modern Power Using Retro Parts!
Replies: 114
Views: 2009

Re: VIC-2000 Expander. Modern Power Using Retro Parts!

I can't imagine a scenario where [changing the ROM character generator] would hurt compatibility. There actually exist quite a few programs that show unexpected behaviour when the contents of the character ROM are changed from the default. For example, the game Astro Nell generates level data from ...
by Mike
Wed Nov 01, 2017 11:36 am
Forum: Programming
Topic: MINIGRAFIK batch processing suite
Replies: 47
Views: 16654

Re: MINIGRAFIK batch processing suite

These days I had some fun porting a nice demonstration graphic from a C16/C116/+4 BASIC tutorial over to MINIGRAFIK. :mrgreen: saturn.zip 10 GOTO28 11 : 12 X=0:Y=B:S=B*B:T=A*A*(2*Y-1):U=2*B*B:V=2*A*A:E=0 13 X1=MX+X:Y1=MY+Y:P1=X1>=0ANDX1<80:P2=Y1>=0ANDY1<192 14 X2=MX-X:Y2=MY-Y:P3=X2>=0ANDX2<80:P4=Y2>...
by Mike
Wed Nov 01, 2017 11:10 am
Forum: Hardware and Tech
Topic: VIC-2000 Expander. Modern Power Using Retro Parts!
Replies: 114
Views: 2009

Re: VIC-2000 Expander. Modern Power Using Retro Parts!

Please note: the VIC can access everything of the internal RAM ( normally $0000..$03FF and $1000..$1FFF, but check out my VFLI mod!) for (text) screen data and RAM based character data. Furthermore, the colour RAM is 1K nibbles in size and spans the address range $9400..$97FF (as seen by the CPU, VI...
by Mike
Mon Oct 30, 2017 1:18 pm
Forum: Hardware and Tech
Topic: 6561 Die Shot Reversing Explorations
Replies: 54
Views: 830

Re: 6561 Die Shot Reversing Explorations

At some time in the raster VIC-I needs to reload/latch the number of columns for a down-counter ("number of columns left for display") - preferably shortly before the border colour could be displayed. At roughly the same time, it is also necessary to decide whether the next raster forms a ...
by Mike
Sun Oct 29, 2017 4:53 am
Forum: Hardware and Tech
Topic: VIC-2000 Expander. Modern Power Using Retro Parts!
Replies: 114
Views: 2009

Re: VIC-2000 Expander. Modern Power Using Retro Parts!

[...] I will get 528 x 368 VGA from the VIC's 176 x 184 image. [...] This is going to be cool... a custom scan converter that lays pixels in a 176 x 184 grid. Maybe you shouldn't fixate too much on the pixel dimensions of the "standard" text screen. The VIC-I is able to re-size and re-pos...
by Mike
Thu Oct 26, 2017 12:01 pm
Forum: Hardware and Tech
Topic: VIC-2000 Expander. Modern Power Using Retro Parts!
Replies: 114
Views: 2009

Re: VIC-2000 Expander. Modern Power Using Retro Parts!

Radical Brad wrote:Pins 20 and Y on the expansion port are free, [...]

In the CR variant of the VIC-20 mainboard, pin Y serves as AUDIO IN.

VIC-20 HAM mode perhaps?

You know the benchmark. ;)
by Mike
Wed Oct 25, 2017 2:28 am
Forum: Hardware and Tech
Topic: VIC-2000 Expander. Modern Power Using Retro Parts!
Replies: 114
Views: 2009

Re: VIC-2000 Expander. Modern Power Using Retro Parts!

On my NTSC enabled VGA monitor (above photo), the VIC actually looks great. Of course it does. :) With the crisp VGA, shown above, I could probably do a 6x6 font and get a 29 x 30 char display instead of the original 22 x 23. People have been doing a 40x24 text display (on a stock VIC-20, just with...
by Mike
Mon Oct 23, 2017 2:32 am
Forum: Programming
Topic: ?FORMULA TOO COMPLEX
Replies: 11
Views: 288

Re: ?FORMULA TOO COMPLEX

Anybody ever witnessed a "?FORMULA TOO COMPLEX" error from a CBM Basic V2.0 program (that is, without any extensions or ML additions). To my opinion, this error can never occur. Can you think of a program (line) that proves otherwise ? The stack for string expressions is only 3 strings de...

Go to advanced search