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I have a few pretty easy questions here, since it could save a couple bytes during certain conditional jumps, and additions if it works. So for example if I lda #$00, the zero flag is set. But what happens if I load a non-zero value? Is the zero flag cleared or unaffected? Does the state of the carr...

So I've been wondering if all the reset button on the console does is merely copying the reset vector to the program counter, or more? Does a hardware reset cause any changes to the PPU or the APU (resetting the channel sequencers or whatever) , and if so, does everything return to an unknown state ...

Alright, I've finally started working on this, and at least I think I'll get this. It's not like you people figure out everything the first time in a matter of seconds, right? (Because I feel like an alien here, my brain is wired for art stuff and not exactly "science" stuff like this, but that does...

I would use it in a game if anything (I want to get better at programming by doing something with the part of the NES I'm the most familiar with) and sound effects would only be played with the Pulse 2 and Noise channels. The SFX data format is simply 16 note bytes (raw period for noise straight awa...

Hey! It's been a while since I last posted anything, mainly because I never had time to even attempt working on anything, but then I realised that these things take a while anyway to make. I don't exactly know what I'm after, maybe all I'm gonna do is just a simple sound engine, maybe more, but I ha...

Hey! Now that I had a little go at 6502 asm with the DPCM hack for Megaman 3, I've been thinking of going out there and starting up some sort of a project from scratch! NROM-256, vertical mirroring, nothing fancy for now. Overall, I understand everything I need, to make a game, at least I say that n...

Oh, yeah I figured out that it wasn't actually my programming that failed, but rather me translating the sequence data to hex, so things got uneven. I decided to throw a PHP-PLP in there just to be safe, and now it's working perfectly! The thing is though, that since I make it reset the delta counte...

I might get warning for double posting now or something, but noone's going to notice otherwise. I sort of got it to work, but the rythmization isn't quite there, maybe you can spot some sort of a problem in my code, or it might be related to how and when the routine is called by the sound engine. Th...

Alrighty, update! After a good 1 week of failing and only getting so close that I actually made a turbo controller out of the basic one, I decided to go ahead and use the code from tepples. (Thanks for that!) It still involved a tiny bit of work because I had to chop the code up and spread the piece...

Oh I'm an idiot, yeah that's probably what I meant, thanks. Edit: Yeah, this doesn't really work either. The bits are kind of the wrong way around now, and in the original game, my input is always seen at $16, flashes for a fraction of a second at $14 and I can't see a thing at $00 when I press some...

Actually that's fine because getting rid of the code for the second controller is of no consequence really. But yeah, I've been meaning to learn all this, it's just that when I think about how much stuff there is, suddenly there's no wonder why there were so many people developing a single game. I j...

The problem isn't that I have no idea what I'm doing. I've been hacking for what...4 years now? The problem is that when I wanted to actually practice 6502 asm, I could never find any assembler that worked for me. They're either all DOS or x32 based, so I can't really run them at all, or they're lik...

Alright guys, sorry for wasting everyone's time. This is clearly not for me. I've spent the last 3 hours fiddling around and nothing worked. I don't have proper assembly tools, nothing's working on my computer, I can't translate any code to hex properly, and I wish I could punch someone right now. I...

This would be for a romhack basically. It's quite simple. Bank $1F is always loaded to $E000-$FFFF and never once swapped. There's enough unused junk data here for me to replace, although most of the are in very inconvenient spots, as I can only read from every 64th byte. There's enough space for a ...

Do you have a disassembled listing of the existing controller reading routine, starting where it writes to $4016? Yeah I have a "complete" but mostly undocumented disassembly for Megaman 3 that I found. I hope this is the right thing. I just simply located where it writes to $4016 (and reads from a...