nesdev.com

I've had the uncanny experience of "getting beaten" by this compiler. I have a function that is simple but running very often, so I tried rewriting the main part of it in asm. It turned out slower than the C version, by more than just the JSR/RTS penalty from calling the asm subroutine. The asm rout...

The only manuals I've seen look like one they'd leave in the hotel room for the user, there probably is a service manual somewhere though, I don't know if it's been found. I'd imagine the circuit would be pretty similar to the NES schematic though, with the extra stuff bolted on. https://problemkapu...

Seems like it should be possible to rip patches from a VGM file . I'm assuming the parameters don't/can't changed while the note plays (I'm not well-versed in the Yamaha stuff), one could store the channel's current register settings when a note-on is triggered. Discarding duplicate sets, and parsin...

This link also has info on the built-in functions, popa, popax, etc. (I know it's linked the in other article, but in case anyone missed that) https://github.com/cc65/wiki/wiki/Parameter-and-return-stacks I don't have a ton of experience doing this, but I did successfully use parameters in this proj...

So we need to get in contact with WhoaMan somehow to fix this? Yes, that's the only way now. Previous version of phpBB used to allow editing through the admin control panel, but it only saved to a cached copy. Next time someone hits the "flush cache" button (or whatever else could cause that), the ...

Non-fatal CPU glitches can happen, I think I've seen a few of them, but it's really rare to do something other than immediately crash. Maybe take a look at Contra's IRQ/BRK vector? Capcom games like to point it to the reset, some stuff just points to an RTI. Tecmo Bowl has a debug screen on BRK that...

Does sprintf (or any other function needing vargs) not work at the moment / not work at all? It seems to copy the format string if there are no placeholders and no vargs supplied, but otherwise appears to do nothing at all. I really don't even need sprintf, I just need a quick way to convert an int...

I mentioned this problem to kevtris, and he had some suggestions: - check PIC config bits, and make sure power-up delay is turned off. Could be that the SNES and SNES Jr. have different reset lengths, and the PIC wasn't out of reset yet. - use provided hex file rather than build from source. Microch...

If it helps to have a simple list (for NES only), there's always the old boardtable.txt
https://wiki.nesdev.com/w/index.php/Board_table

Are you saving and restoring registers in your interrupt handlers by pushing them to and pulling them from the stack? If not, then if an interrupt occurs between these instructions, your registers will likely be clobbered. Yeah, I think it's that. And if the NMI is itself being interrupting by anot...

Is there an SNES emu that will let you view the contents of palette RAM? If so, copy a sequence of values, and search for them in a save state from the same screen.

It is some incredible timing, I don't think have been new C compilers for decades. I think the difference is that VBCC is a mature compiler with a new 6502 backend, while KickC is an all-new 6502-specific compiler. It's really interesting, seeing all the code fragments and how you can add new ones. ...

Btw. if you declare the function pointer arrays like this static void (*const addrtable[256])() = { ... static void (*const optable[256])() = { then they will be placed in ROM only rather than being copied from ROM to RAM. Thanks for the tip, changing those to const does fix it, and with that fake6...

One of the more absurd programs I've put together, this demo uses fake6502 by miker00lz, compiled with cc65, to emulate a 6502. The emulated 6502 remaps NES internal RAM to $7000 and a portion of $6000+ (that cc65 uses) to $7800. This emulated 6502 boots from the ROM's own reset vector, which in tur...

Thanks for getting it to build, lazycow. My cat also likes this demo, haha. I did notice another thing in lnAddSpr that could be optimized, maybe a little controversial though. The INX INX INX INX sequence could be replaced with TXA / AXS #$FC unofficial opcode (it trashes A, but the loop trashes it...