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Alright I guess I'll need to do this over with the nes $2000 & $2001 bits. Sucks cause I'm at the part where I am converting the chr data, wish I understood better earlier. My new plan is to break down those bits from nes $2000 $2001, have DP registers set aside where they get modified correctly...

sorry i guess i am misunderstanding the TSB TRB, figured resetting a bit, would be the same as simply writing a 0 to it, i'm going to have to halt my progress to get this worked out.

Hmm, having issues where my bg 1 tilemap location keeps getting removed even though I'm no touching it. I have massive routines that check for the way the games original mirroring Nametable is, and I reset/set bits to the $2107 registers #2 #1 bits, aka #0-#3 to determine 32x32 64x32 32x64 64x64. No...

Hmm. I dont have any readability of $4211, where should I place the read? Edit - I placed a read at the only irq that is loaded for the time being, and I think I'm ok. My port and the original rom are now at the same location, phew! Onward with figuring out the loading from other banks. Edit 2 - Dis...

I keep getting my irq vector loading over and over, ugh, not sure why. I have a routine that makes A 16 bit, and when it comes time to load A as 0000, I get hit with an irq interupt, and I'm unable to get back to my routine, it starts pushing to the stack while I'm in 16bit mode, and then the irq is...

I disagree that the status flag changing is "normal". Nothing should affect the IRQ disable flag except for SEI, CLI, SEP, REP, or PLP instructions. Something is not right, and you should investigate that, rather than a workaround solution. Running a trace log, and advancing one frame at ...

34 vs 30 is normal, interrupts will set the interrupt flag just after pushing P. If the first instruction within NMI code is PHP, the stack may look as follow: 34 30 I understand what you're writing, but what doesnt make sense is why the irq was being triggered for the 3rd interrupt, but not my NMI...

Well it wasnt the irq that was causing my stack issue. Turns out it deals with my "P" status. During my reset vector loop, the nmi never fires at the same exact spot in the loop. The last moment before the first NMI fires, it pushes the P status to the stack, and when the NMI first fires, ...

You sure it's not an IRQ or BRK $00 and your IRQ or BRK vectors point to $0000 ? :shock: sigh, whoops, didnt have the irq vector pointer set. Yes before my snes init code I have CLC,XCE. What happened was since I'm from the NES side of things, I had $FFFE-$FFFF set, $FFEE-$FFEF was all 00's. I forg...

Yeah I think that's it, still doesnt explain by the time my NMI is supposed to fire up for a 3rd time, it doesn't and brings me to $0000 Technically its not the point of the NMI being fired up for a 3rd time, the nes rom forces an address into the stack, and its supposed to goto that address. This w...

Yup, I work entirely via hex, been coding that way since 2004. It's 2021. This could be the year that you finally switch over to an assembler 8-) Really though, working with an assembler isn't that bad. I mean, your projects are ambitious and impressive. I loved your NES zelda hack (more of a new g...

Felling good! Created a new routine so that the original games current buffered bg/sprite palette id's, are converted to their 16-bit equivalent, stored into an area in wram for my 200 byte table to be uploaded into CGRAM, and uploaded via DMA. ;setup indirect indexed addressing to $70-$71. lda #$40...

Crap cause I have a good sized routine that sets and resets bits TRB/TSB on $4200.....

Ok, so I started experiencing an issue where my NMI wouldn't fire back up for a second time. I did some investigating, and I came to my mmc3 irq setup. IRQ HV enable is included in $4200. As bits 2# and 1#. Now, before this routine i had set the NMI enable 8# bit in $4200. And later on I come to the...

I was editing my previous post when you showed back up, and you may have missed a detail. In any case I might as well be explicit about this, just in case you don't already know: The SNES has two bank registers: the program bank and the data bank. They are not the same thing and can have different ...