Search found 41 matches
- Sun Apr 28, 2024 11:40 am
- Forum: Programming
- Topic: 3D Stars
- Replies: 15
- Views: 8468
Re: 3D Stars
My suggestion would be to normalise this so it's integer-based. They're always faster than FP calculations. You could then use X% and Y%, and so forth, which I think speeds up the interpreter. You could also unroll the GOSUB calls, though that's a personal call.
- Fri Apr 19, 2024 10:20 am
- Forum: Emulation and Cross Development
- Topic: ASM502 - a new 6502 assembler.. (WIP)
- Replies: 22
- Views: 15018
- Thu Apr 18, 2024 9:19 am
- Forum: Emulation and Cross Development
- Topic: ASM502 - a new 6502 assembler.. (WIP)
- Replies: 22
- Views: 15018
Re: ASM502 - a new 6502 assembler.. (WIP)
During assembly, keep a hold of the state of the machine and comment on instructions that do not affect that state. For example: if it can be known that the carry is set, then do not assemble a SEC, but comment in the listing that that instruction was ignored. Same for a memory location that is kno...
- Tue Apr 16, 2024 11:34 am
- Forum: Games
- Topic: Prince of Persia
- Replies: 71
- Views: 52803
Re: Prince of Persia
This is really incredibly good. I've never played Prince of Persia but I've heard so many stories about it: it, and its development, are something out of legend. And here it is on the humble VIC-20... I'm speechless, and profoundly impressed. I don't know the game, but I am curious if it would be po...
- Tue Apr 09, 2024 10:43 am
- Forum: Hardware and Tech
- Topic: Run/Stop Restore doesn't work
- Replies: 3
- Views: 2989
Re: Run/Stop Restore doesn't work
Here's a related question. There are a couple of old VIC games I have which affect RUN/STOP-RESTORE. One of them, Riddle of the Sphinx by Lyversoft, uses POKE 37150,2: this has the effect of entirely locking out RUN/STOP-RESTORE. The other, Four Gates to Freedom by Phoenix Software, has POKE 37150,3...
- Thu Apr 04, 2024 10:36 am
- Forum: Emulation and Cross Development
- Topic: MegaVIC (split from: Introduce Yourself: What's your User Name based on?)
- Replies: 9
- Views: 9065
Re: MegaVIC
M., Gotta get the MegaVIC to be something that ultimately runs on a real 6502 (versus another "emulator" type "system")! :mrgreen: OGM Hi OGM, Actually, I'd rather it ran on my own chip, the 768R32 ;-) 32-bit data bus, 26-bit address bus, 16 registers, SP, LP. WDC meets ARM. :-)...
- Wed Apr 03, 2024 7:40 pm
- Forum: Emulation and Cross Development
- Topic: MegaVIC (split from: Introduce Yourself: What's your User Name based on?)
- Replies: 9
- Views: 9065
Re: MegaVIC
Hi Merytsetesh, I checked the videos. The Elite object rotations are silky smooth. Very nice. Just a thought: It seems you're half way to a Pixelvision or Tic80 type system. So the MegaVIC can be born as something like that maybe? Greetings H Hi Huffelduff, Thank you for the kind words. I can't lie...
- Mon Apr 01, 2024 2:03 pm
- Forum: Buy, Sell, and Trade
- Topic: Any interest? Final Expansion 3 (UK)
- Replies: 8
- Views: 6058
Re: Any interest? Final Expansion 3 (UK)
VIC-1110 servicing memory locations 40960-49151 (8K - DIP: 1000 )* --------- * memory locations not accessible from BASIC At the risk of being picky, block 5 is accessible by BASIC through the use of POKEs: it's just not usable by the BASIC interpreter for code by reason of being discontiguous from...
- Mon Apr 01, 2024 12:56 pm
- Forum: Emulation and Cross Development
- Topic: MegaVIC (split from: Introduce Yourself: What's your User Name based on?)
- Replies: 9
- Views: 9065
Re: MegaVIC
I'd be interested! What is a MegaVIC? For a little bit of background, the MegaVIC started out as a simple CBM BASIC 2 interpreter built in Python. It was something I had always promised myself I'd write, and over COVID, and having to spend a lot of time at home, I got down to writing it. It didn't ...
- Sun Mar 31, 2024 11:00 am
- Forum: Buy, Sell, and Trade
- Topic: Any interest? Final Expansion 3 (UK)
- Replies: 8
- Views: 6058
Re: Any interest? Final Expansion 3 (UK)
Oddly, I've just found this seller, who seems to be in the US.
srowe, would your cartridge look like an old-style VIC cartridge?
srowe, would your cartridge look like an old-style VIC cartridge?

- Sat Mar 30, 2024 8:36 am
- Forum: Emulation and Cross Development
- Topic: Assembler
- Replies: 38
- Views: 22243
Re: Assembler
Finally got wAx2 working last night. For some reason the .crt file I downloaded from GitHub was corrupted, which is why it wouldn't settle into VICE. (I've also experienced a similar problem with the manual PDF.) I ended up downloading the .eep and using cartconv to get it to work. And now... ... an...
- Wed Mar 27, 2024 2:44 pm
- Forum: Emulation and Cross Development
- Topic: Assembler
- Replies: 38
- Views: 22243
Re: Assembler
I have been trying to use wAx2 with VICE and I cannot get the dratted thing to settle into memory. I found a link to a GitHub repo with .PRG and .CRT files and the wAx2 manual, but no amount of persuading seems to get VICE to be willing to install it as a cartridge. I am sure, as usual, I am missing...
- Mon Mar 25, 2024 1:17 pm
- Forum: Programming
- Topic: Line drawing algorithm
- Replies: 55
- Views: 25124
Re: Line drawing algorithm
Given x2>x1 and y2>y1, a line on screen looks like a backslash, "\", assuming a left-handed co-ordinate system. You can't enforce y2>y1 though when the endpoints already have been sorted for x2>x1, as that would exclude lines that look like a slash, "/". Of course, and I'm an id...
- Sun Mar 24, 2024 12:01 pm
- Forum: Programming
- Topic: Line drawing algorithm
- Replies: 55
- Views: 25124
Re: Line drawing algorithm
First off, I'd like to take my hat off to you, Mike: this is incredible. I would never have looked at things from this perspective -- not for a long time, anyway. Getting 20K-30K px/s on a VIC is incredible. Everything here is a masterclass in elegance in engineering... I'm lost for words. Another s...
- Thu Mar 14, 2024 10:34 pm
- Forum: Programming
- Topic: A sample programming session in VICMON
- Replies: 32
- Views: 31160
Re: A sample programming session in VICMON
When the value already is in the Accumulator, then using 2s-complement is shorter and faster - and it can even spare the CLC instruction when the state of the carry flag is known at that point, doing either EOR #$FF/ADC #$01 when C is known clear or EOR #$FF/ADC #$00 when C is known set. See here ....