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Oh thank you! So it's sort of an automated way of creating variables, which could be global or local to a bank I declare them in I suppose. .enum $0000 temp_0 .dsb 1 temp_1 .dsb 1 ;... .ende So does that mean that when I say lda temp_1 it's going to load from $0001? Not that it really matters as lon...

So I have a couple problems with variables and constants, and having looked at the templates made by tokumaru it's even worse in my head now. I've always been "declaring" variables simply by naming the RAM offsets like: temp_0 = $00 These are all in a separate "RAM map" source fi...

So I'm back and every now and then when I have some free time I'd like to exercise my brain in a productive way and do some stuff with the NES! Preferably a game project. And no matter what, there are two things that scare me when it comes to planning development. 1. Which are the best and most comm...

I honestly don't think it's fair to include home computers in this list because they were not design solely for the purpose of running games (despite that the C64 got the SID which is anything but necessary for a business machine) I just want to go ahead and praise/bash the SMS hardware. Graphically...

Hmm, I'm a little worried because I use the sweep units for percussion, (and I could create an instant cut command later) but what if the channel is silenced due to overflow from the sweep unit adder, or because of a period less than 8? Do I have to write to the length counter of the channel to rest...

That does seem like a good idea now that I realised the operation of the stack is not lethal to data you just write to $0100-$01FF. If pushing and pulling only affect S it's fine for this. I thought stack affecting operations rotate bytes as well, and whatever is at $0100 is lost if I push something...

Alright, now comes the final stretch. I got it to work, sort of. The triangle and noise channels work perfectly after a little bit of debugging and adding safety measures, and the whole thing is stable so I just need to find out what's wrong with the pulse channel code. Which brings me to a question...

So it's come to this yet again. So many really little things I just need to ask, but thank you all of you for the help up until now, you're aiding me to set sail and explore the amazing waters of asm and it's a wonderful experience (and who knows if I get experienced who's to stop me from moving on ...

I've got a question coming in from a friend, basically the thing is, he really hates how short the cables of the Famicom controllers are and wants to know if the standard is the same as the NES controllers, which would make it possible to cut the Famicom and NES controller cables, and solder the NES...

This lda susoff_flags cpx #$02 bcs ClearPu2 This decides which channel bits have to be cleared. X serves as an index, depending on which channel's turn it is 00 means Pulse 1, 02 means Pulse 2, 04 = Tri, 06 = Noise I don't know why I included the lda, but that's where I load, and then select a value...

Ah ok, that makes sense. It's just simply the context that made it confusing for me, because the only thing that matters is that certain bits must be cleared by this code, it doesn't matter if I flip them or AND them with the right 2's complement, because when this fires off, both bits are 1 always....

ORA & EOR vs. ADC & SBC So the situation is the following: Sometimes I need to set or clear certain bits in memory, but without affecting the rest of them. I figured this could be done by simply adding or subtracting in binary, but sometimes that bit is already set/clear, so a remainder is c...

You're loading a value from $E704, which is part of the cartridge space, so it'll only happen if there's the $FF as a constant at $E704
I don't know which assembler you're using, so you might have to change the .db to .byte

Implementing DPCM *could* be the easiest thing to do if it wasn't for the controller port/PPU data reading bugs introduced (of which you probably only need to worry about the former) But playing a DPCM sample by itself is incredibly easy. First I advise turning it off by writing $0F to $4015 You sim...

I never use the length counters for anything. My pulse channels are fed with volume/duty register writes every frame from a table accessed via a table of pointers (these are the instruments), so it's just a matter of always sending the correct bit to keep the length counter disabled. The triangle wi...