Search found 1060 matches
- Thu Oct 19, 2023 9:26 am
- Forum: Emulation and Cross Development
- Topic: VICE key-rollover inconsistencies
- Replies: 3
- Views: 2063
Re: VICE key-rollover inconsistencies
I have implemented (partial) emulation of the Keyboard matrix quirks some years ago - indeed only for C64 (and C128 i believe). Even for those, it doesn't really work right in all cases (but good enough for 3 keys i think). It's quite a surprisingly complex problem unfortunately :) So no, you are no...
- Wed Oct 11, 2023 4:51 am
- Forum: Hardware and Tech
- Topic: Making a cheap Power supply.
- Replies: 5
- Views: 2211
Re: Making a cheap Power supply.
VIC20, yesIt'll work - mostly - if you don't connect anything at all to the 9VAC pins. That voltage is used on the user port for things like RS232 and some modems, and also for the datasette motor.
- Fri Oct 06, 2023 1:37 pm
- Forum: Emulation and Cross Development
- Topic: Stack Watching in VICE
- Replies: 21
- Views: 4186
Re: Stack Watching in VICE
rhialto made a quick patch
http://www.falu.nl/~rhialto/watchpoints1.diff.txt
eg
break load 0 $ffff if @cpu:(pc) < $80
http://www.falu.nl/~rhialto/watchpoints1.diff.txt
eg
break load 0 $ffff if @cpu:(pc) < $80
- Fri Oct 06, 2023 10:27 am
- Forum: Emulation and Cross Development
- Topic: Stack Watching in VICE
- Replies: 21
- Views: 4186
Re: Stack Watching in VICE
BTW, i am offering a crate of beer to whoever implements a "dereference" operator for the conditions (so you can use the content of the memory whatever expression points to) - that would be super useful indeed
- Fri Oct 06, 2023 8:38 am
- Forum: Emulation and Cross Development
- Topic: Stack Watching in VICE
- Replies: 21
- Views: 4186
Re: Stack Watching in VICE
Unfortunately notCan the value of the memory at PC be used?
- Fri Oct 06, 2023 7:28 am
- Forum: Emulation and Cross Development
- Topic: Stack Watching in VICE
- Replies: 21
- Views: 4186
Re: Stack Watching in VICE
I don't think this can be done directly (please correct me if i am missing something) - you can only compare registers and memory locations, there is no way to tell "was pulled from stack". Perhaps you can do something like ($100+SP)=$55 && A=$55 (which is obviously not really what...
- Mon Oct 02, 2023 5:21 am
- Forum: Programming
- Topic: C=Hacking Issue 8 - fast plot routine with 20 cycles
- Replies: 7
- Views: 2255
Re: C=Hacking Issue 8 - fast plot routine with 20 cycles
Next step would be unrolling the loop for each needed slope... perhaps not on VIC20 though
- Fri Sep 22, 2023 3:27 pm
- Forum: Games
- Topic: Crazy Cavey
- Replies: 11
- Views: 2796
Re: Crazy Cavey
Raster tricks are actually easier than on VICII - since there are no "bad lines". Very straight forward
- Fri Sep 22, 2023 2:35 pm
- Forum: Hardware and Tech
- Topic: Making a cheap Power supply.
- Replies: 5
- Views: 2211
Re: Making a cheap Power supply.
I don't think you'll fry something - but it will not work
- Wed Sep 13, 2023 12:08 pm
- Forum: Hardware and Tech
- Topic: I/O0 and illegal opcodes
- Replies: 9
- Views: 2633
Re: I/O0 and illegal opcodes
All the modern loaders doAlso I know the C64-fastloader Spindle uses illegals to do GCR-decoding on the fly which was deemed impossible before.
- Wed Sep 13, 2023 9:53 am
- Forum: Hardware and Tech
- Topic: I/O0 and illegal opcodes
- Replies: 9
- Views: 2633
Re: I/O0 and illegal opcodes
but there does exist software that uses the so-called "illegal opcodes". To add to this: not seldom in old games there are undocumented opcodes executed not because the coder used them intentionally, but because they are a result of accidental memory corruption during development. (This i...
- Sun Sep 10, 2023 11:22 am
- Forum: Other Systems
- Topic: New Release: PETSTRIP for PET/CBM 3032 and 4032
- Replies: 5
- Views: 2162
Re: New Release: PETSTRIP for PET/CBM 3032 and 4032
This is really very cool. Imagine showing this to ppl back in 1980 :=)
- Sun Jul 02, 2023 5:22 pm
- Forum: Programming
- Topic: Need help converting multicolor font from atari to commodore.
- Replies: 1
- Views: 1081
Re: Need help converting multicolor font from atari to commodore.
As said on Lemon - can't you simply use it as is? The binary format should be the same
- Sun Jul 02, 2023 5:37 am
- Forum: Other Systems
- Topic: Help modifying C64 PAL code for NTSC machine
- Replies: 5
- Views: 2300
Re: Help modifying C64 PAL code for NTSC machine
It uses PB7 indeed, and that's L - correct
The problem might indeed be the video source - if the video was deinterlaced, ie is now 25fps, then it will probably not work
The problem might indeed be the video source - if the video was deinterlaced, ie is now 25fps, then it will probably not work
- Sat Jul 01, 2023 7:23 am
- Forum: Other Systems
- Topic: Help modifying C64 PAL code for NTSC machine
- Replies: 5
- Views: 2300
Re: Help modifying C64 PAL code for NTSC machine
Generally on NTSC everything needs to be 20% percent faster (50Hz PAL vs 60Hz NTSC). So, when you you look at the code, there is one delay loop at $c044 which is called with different values in X at various places. So the first/easy attempt is to make this delay loop 20% faster (which then means all...