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The opcodes I'm keeping the same just as it is in NES. For now, until I make sure I have a successful port, A,X,Y are all 8 bit, the only time I switch any to 16 bit, as for when it comes time to edit the stack low address.

Ok i apologize for misunderstanding the lazy remark. Ive used this exact method in my MMC5 Legend of Link romhack I did back in 2014, where I was able to have an extra prg-rom to work with, because my dpcm samples are 3 quarters of my $c000-$ffff. I'll ditch the SA-1 idea. I'm coding everything via ...

I wanted to keep the code the same length as possible throughout the rom, so that no branches get messed up, or no called routines are moved and crash the rom, i dont consider it lazy with the method im currently doing, I'm just trying to be very careful not to miss anything during this port. Regard...

PM sent.

I just saw a video discussing the SA-1, and how it has a Super MMC. Would I be able to make it so that any time I access $C000-$FFFF anywhere in the rom, that that region will always be in bank 00?

Well right now i'm progressing through code perfectly, just like the NES code is doing. I'm now at the point where i'm setting up the startup ASM from that game. It's all because of adding that AD1042 right after my pushes at the start of my NMI. The code ive been putting in has been working correct...

This is the code that is kicking me back to my NMI prematurely. What I am doing is with this port, making sure i match the nes ppu addresses that use bits, to match what would be used on the SNES. What i'm doing here is taking the value that is in register $FF of the NES, which deals with setting $2...

I'm sorry, the code I posted is in the reset vector. This is the routine that deals with timing, waiting for however many cycles to pass on the NES. The code I pasted for the SNES equivalent, I wanted to see if that is correct. I do make it to my NMI with what I've shown, but overtime within the NMI...

Ok so I'm getting some issues within my NMI, it keeps filling up my stack. I'm going to sift through my code, but I wanted to know if I'm doing the NES $2002 properly on the SNES, I've included 2 screenshots. https://i.ibb.co/bg8Ry6n/Screenshot-20210306-204147-Gallery.jpg https://i.ibb.co/tD9skBB/Sc...

The nes game I'm porting, uses F8 for the sprites Y position to hide it off screen. And the leftmost masking the NES has, you're saying I can replicate that feature on the SNES? As of right now I'm not near the point where the vram routines begin. I'm still in the rest vector getting all my initiali...

The game I'm porting uses 8x8 sprites. If I have to relocate the sprite DMA to $800 it wont be an issue. But if I am able to keep my Sprite DMA at $200-$2FF then I'll keep it there. So I'll wait to see how these responses play out, cause I'm confused now.

Woah, ok. What I'll do then is relocate the Sprite DMA from $200 to $800. And thank you very much for that code!

Ok two things. 1. In the nes, sprites usually occupy NES ram from $200-$2FF. I'd like to keep it that way with my port. My question is, do I use the snes addresses $2102-$2103 to store the snes ram address of $200? 2. For my issue with the nes $2000 bits, I've written up code in the nes game, to bac...

Wow I didn't know about TSB TRB, and I like how you can simply select the bit value in A, and have it set or clear the bit that is select in A. Whereas the old way with NES you have to AND/OR, and make sure you have all the bits set correctly in A before they get stored/cleared. So now I just need t...

Thanks everyone for your responses. I figured it out, my JSL routine I had was so I could switch my XY to 16-bit, so I could change the stack pointer, and RTL back to my code.... No wonder I couldn't get back with my RTL.... *slaps head. I'm not blindly changing the stack pointer btw, the game I'm p...

I'm also having an issue with JSL, I'm trying to RTL back to the bank I was previously in, and it's not working. I've tried pushing the data bank before I initiate the JSL, but I dont see anything get pushed, then I enter the bank i JSL'd too, code gets loaded, i then use PLB, then RTL, and I ended ...