Search found 2897 matches

by Mike
Sat Dec 09, 2017 2:22 pm
Forum: Collecting and History
Topic: Programmer's Aid ROM part no?
Replies: 2
Views: 77

Re: Programmer's Aid ROM part no?

325315-01, according to 6502dude's list.
by Mike
Tue Dec 05, 2017 5:11 am
Forum: General Topics
Topic: GeoRAM on the Vic20
Replies: 5
Views: 182

Re: GeoRAM on the Vic20

The I/O areas on the C64 are also 1KB. Erm, no. The I/O address range on the C64 is partitioned as follows: $D000..$D3FF: VIC $D400..$D7FF: SID $D800..$DBFF: colour RAM $DC00..$DCFF: CIA #1 $DD00..$DDFF: CIA #2 $DE00..$DEFF: I/O 1 for cartridge port, 256 bytes $DF00..$DFFF: I/O 2 for cartridge port...
by Mike
Sun Dec 03, 2017 10:40 am
Forum: Collecting and History
Topic: Possible MOS tech docs find
Replies: 2
Views: 103

Re: Possible MOS tech docs find

I merged above two posts, one from the Hardware section and the other from the General topics section into one thread thread here in the Collecting and History section.
by Mike
Fri Dec 01, 2017 11:38 am
Forum: Hardware and Tech
Topic: VIC-2000 Expander. Modern Power Using Retro Parts!
Replies: 131
Views: 2990

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

Look, I've been in the field of programming for over 30 years now. That skill not only involves writing good code, but also being able to read, understand and value other people's code. Exactly that statement "I [...] never use anyone else's code in my projects" tells me, that however good...
by Mike
Fri Dec 01, 2017 10:20 am
Forum: Hardware and Tech
Topic: VIC-2000 Expander. Modern Power Using Retro Parts!
Replies: 131
Views: 2990

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

Radical Brad wrote:I also have a rule to never use anyone else's code in my projects.

Sigh. :(
by Mike
Fri Dec 01, 2017 9:48 am
Forum: Hardware and Tech
Topic: VIC-2000 Expander. Modern Power Using Retro Parts!
Replies: 131
Views: 2990

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

No basement hacking time lately, but I did manage to code up a decent keyboard scan routine. It takes a bit of effort to make a low cycle count keyboard decoder when you are doing your own row and column scanning routine. Well, there's nothing too embarassing wrong with the KERNAL's original keyboa...
by Mike
Thu Nov 30, 2017 11:35 pm
Forum: Programming
Topic: ** New Frontiers in VIC-Hires-Graphics, Part 4
Replies: 17
Views: 3253

Re: ** New Frontiers in VIC-Hires-Graphics, Part 4

Hi, Armando. I had to ask tokra, if he still had a copy of those two demonstration programs I sent him 7 years ago. That turned out with a positive result - for myselves, I couldn't find no trace anymore of those on my HDD: 208x208_demo.zip 'plot.prg' contains the pixel plot routine converted to mac...
by Mike
Thu Nov 30, 2017 12:48 pm
Forum: Hardware and Tech
Topic: Vic20 Vixen Switchable 16k RAM Expansion Repair
Replies: 14
Views: 269

Re: Vic20 Vixen Switchable 16k RAM Expansion Repair

The thing with Vixen is, there's only two binary switches, so that's why the memory options are 0, 3, 8 and 16. You'd need to sacrifice one of those options to allow for 24k or 35k in there. Everything that requires +8K should also run with +16K, +24K and +32K (the latter with 8K in BLK5). Likewise...
by Mike
Thu Nov 30, 2017 3:08 am
Forum: Hardware and Tech
Topic: Vic20 Vixen Switchable 16k RAM Expansion Repair
Replies: 14
Views: 269

Re: Vic20 Vixen Switchable 16k RAM Expansion Repair

That would make it able to play about 3 more games right? If you only go by what's available at ftp.zimmers.net , yes. However, that's not the last word on this (see here ), and VIC Doom requires +35K RAM (i.e. an extra +3K RAM expansion alongside your possibly enhanced +16K -> +32K RAM expander), ...
by Mike
Sat Nov 25, 2017 3:46 pm
Forum: Programming
Topic: VIC-20 Startup Sequence
Replies: 4
Views: 125

Re: VIC-20 Startup Sequence

I also don't know how the VIC would determine if ROM is installed in BLOCKS 1,2, and 3. It can't exactly do a write and read test on those locations. So that makes me wonder how then it would know to relocate the screen memory? Of course a R A M check is part of the KERNAL reset routine. The RAM ch...
by Mike
Sat Nov 25, 2017 3:14 pm
Forum: Programming
Topic: VIC-20 Startup Sequence
Replies: 4
Views: 125

Re: VIC-20 Startup Sequence

A thorough look at the reset routine beginning at $FD22 is wholeheartedly recommended. :mrgreen: Of course it's the KERNAL that starts up your cartridge, so at least something happens before your code runs. If you want to set up memory and I/O properly, yet still remain in control, you'll at least h...
by Mike
Sat Nov 25, 2017 1:39 pm
Forum: Programming
Topic: MINIGRAFIK batch processing suite
Replies: 48
Views: 16803

Re: MINIGRAFIK batch processing suite

This (slightly longer) post covers a MG tool package (download at end of post), which does huge global changes to a picture. To be more specific, the programs of this package facilitate to remap the colour sources. This comes in quite handy, if a draft done in MINIPAINT suggests it might be better t...
by Mike
Sat Nov 25, 2017 10:26 am
Forum: Programming
Topic: MINIGRAFIK lineart
Replies: 12
Views: 381

Re: MINIGRAFIK lineart

... perhaps you had something like this in mind? 10 @ON:@CLR:@1,130,50TO70,150:FORT=1TO72:READX,Y:@1,15,25TOX,Y:NEXT 11 GETA$:ON-(A$="")GOTO11:@RETURN:END 12 : 13 DATA 159,25,159,4,100,0,71,0,56,0,47,0,41,0,36,0,33,0,30,0,28,0,26,0,24,0,22,0,20,0 14 DATA 19,0,18,0,16,0,15,0,14,0,12,0,11,0,...
by Mike
Sat Nov 25, 2017 6:13 am
Forum: Programming
Topic: 320x200 - a CGA emulator for VIC-20! (+35K RAM req'd)
Replies: 7
Views: 845

Re: 320x200 - a CGA emulator for VIC-20! (+35K RAM req'd)

[...] a converter from 4 colour *.ppm files is in the works. Here we go: ppm2cga.zip When you double-click 'ppm2cga.cmd', the *.exe will quantize the file 'input.ppm' (strictly 320x200 pixels and a 24 bpp *.ppm file) and write the files 'result.ppm' (preview on PC) and 'result.seq' (for use by the ...
by Mike
Fri Nov 24, 2017 7:04 am
Forum: Hardware and Tech
Topic: VIC-2000 Expander. Modern Power Using Retro Parts!
Replies: 131
Views: 2990

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

The reason for the digital noise is due to the way I slapped this all together for testing. When the VIC does "POKE 38917,0", it is triggering the WE line to go low on the frame buffer SRAM. That same line attempts to disable the counters that are actually generating the video frame. Beca...

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