Denial

Try MAME Debugger? It's not source level, but it's way better than VICE for VIC-20 out of the box. You can load in a comments file with text comments to be displayed along side the disassembled source, the on-screen layout isn't perfect, but it's usable. https://github.com/phillipeaton/JETPAC_VIC-20...

$16,$03,$2D,$32,$30,$20,$20,$20,$04,$09,$01,$07,$0E,$0F,$13,$14

16 is 22 decimal, V is the 22nd letter in the alphabet
C s the 3rd letter

04 is D
09 is I
01 is A
07 is G
...

Seems simple, unless I'm misunderstanding the question?

Here are some 6502 C compilers benchmarks: https://gglabs.us/node/2293 Not mentioned is Oscar64, but the author tested it himself, 3 run each, with the following results. It's on Github, maybe check it out? 1 crc8 1.2 1.2 1.2 2 crc16 1.8 1.7 1.7 3 crc32 3 3 3 4 sieve 13.1 12.7 12.8 5 sieve bit 20.3 ...

Ola H wrote: ↑Thu Mar 07, 2024 7:06 pm ... and it is great to learn just how the flying routine managed to produce such a great feeling and perfect responsiveness.

Thanks for your thoughts. Yes the flying routine is complex, more than I imagined at the start!

I use the Kingwood Consulting cross-assemblers, they're pretty straightforward to use, plus they have Linux and Windows versions:

https://www.kingswood-consulting.co.uk/assemblers/

My reverse-engineering of JETPAC for the VIC-20 is now complete. It's been a big learning experience, about the VIC computer itself, the tools and my own motivation and ability. Check it out if you're interested, see what you think, comments appreciated. https://github.com/phillipeaton/JETPAC_VIC-20...

Once you get it assembled to a binary image, you might consider single stepping the code it in MAME Debugger, I've successfully debugged someone else's broken code this way. MAME Debugger is very robust and has good options for live viewing memory in resizeable windows and setting breakpoints, much ...

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I'm still plugging away on this whenever I get a spare minute in the evenings, the end is in sight! Someone asked me for an intro of how I'm doing the reverse engineering, so I made a little video show 'n' tell. Any hints and tips to improve my efficiency, much appreciated! https://youtu.be/exYrwbS1...

...p.s. looking forward to you using it to implement Sabre-Wolf on the 35k Vic :D Sabre Wulf didn't really cross my mind, but I just looked on YouTube and the usage of sprites is very similar to JETPAC. A conversion would certainly be doable, though the 16x8 pixel colour tiles used in VIC JETPAC wo...

I would recommend 6502bench SourceGen as a disassembler. You can work with it interactively to help with the distinction between code and data. It provides automatic labelling of subroutine calls, jumps and branches. It also allows you to add comments and notes which I found particularly useful. Th...

Hi! [...] JETPAC for VIC. I was always intrigued how the sprites worked, so 40 years later I thought I'd find out. If you follow through that, let me tell you: you quite possibly find only one particular implementation of smooth moving objects on the VIC-20. One that has been tailored to the needs ...

In case anyone's interested, I'm in the process of reverse engineering Ultimate's JETPAC for VIC. I was always intrigued how the sprites worked, so 40 years later I thought I'd find out. I reckon I'm past the point of no return now, perhaps 50% of the way, so I have to finish it. I've spent about 9 ...

List should probably mention MAME instead of MESS, which was absorbed into MAME years ago. VICE is probably the goto emulator for most use cases, but for reverse engineering, as of Feb 2023, the MAME debugger is much better than the one in VICE.

Well, my Vectrex Forth runs from a cartridge and uses a few hundred bytes of RAM, but you're already using block 5, so I guess you'd have to shoe-horn it into block 0, replace the BASIC ROM or do some other shuffling around. You could make a basic usable Forth in perhaps 2 or 3K. If you've already f...