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Hmm, I never even thought of the unofficial opcodes. They are all implemented, but I'm not sure how well they work. They all move the program counter the right number, but that's about all I can guarantee. Three of them fail on test 03 but that's the only test that outputs any opcodes. The other tes...

Thanks for all the helps guys! I should have been using pointers from the start for mirroring - it makes it so much simpler. I rewrote all of my memory functions that have to do with RAM so that almost everything is done through pointers now. However, a new problem has arisen. I decided to run back ...

I completely forgot that I could use pointers to reference data pieces inside of an array. I'll come home and re-write my mirror functions accordingly later tonight with pointers. Here is how I handle writes to registers for those who asked: switch(address) { case 0x2000: ppu->ppuTempAddress &= ...

Of course it was a dumb mistake like that. I checked that function multiplie times and missed it. Now I passed, which means my CPU checks out. After comparing my VRAM dump of Donkey Kong to the one posted earlier in this thread, I'm way off. I'm not exactly sure why, though. I went through and reche...

Well I'm happy to report that I passed every test except for 11-stack. I've checked everything that has to do with the stack, and I cannot find my error. Test output: 48 PHA 08 PHP 68 PLA 28 PLP 9A TXS BA TSX 11-stack Failed I'm guessing that since I'm missing pretty much every instruction that effe...

For some reason only tests 01-03 print out a pass/fail message. 04, 05, and 06 only output the missed opcodes. If no opcodes are missed, then nothing gets printed out. Is that supposed to happen? Here is what I'm getting right now for 04: �ްa P �4 � � /usr/lib/x86_64-linux-gnu/libXdmcp.so.6.0.0 @ ...

Zeropage reads work correctly on nestest.nes, so I don't understand why they aren't here. I pass the ppu to readRAM so that if $2002 is read I can clear the writeToggle or if $2007 is read I can use/increment the ppuAddress. I have a separate function for reading from VRAM creativity called readVRAM...

05-zp_xy gives the same results as 04-zero_page does. The same opcodes are showing up that showed up in the zeropage test.

Here is my code for $A2 immediate LDX:

I passed 01-basics and 02-implied. 03-immediate failed but only on illegal opcodes, so I moved on. Now 04-zero_page is really burning me. I'm not even getting a failed message, just a string of easy opcodes... Output for 04-zero_page: A6 LDX z, A4 LDY z, 85 STA z, 86 STX z, 84 STY z, E6 INC z, C6 DE...

So I've been trying to get my output to dump correctly. My RAM is of type unsigned char and I'm having a hard time figuring out how to print out the output text. If I don't cast the data as (int), gedit refuses to open the output txt document because of "invalid UTF-8 input". So I've outpu...

It looks like I'll have to implement MMC1 to use Blarg's official opcode test from looking at the header. That's going to take some time...and I don't really understand how the output at $6004 works. Do I just dump a range of memory after a while to see what opcodes I missed? As for how I was doing ...

It seems that my CPU was off a little bit. I corrected two small errors and then decided I would add in all of the illegal opcodes as well so that I could complete the nestest.nes test. I wasn't able to find Blarg's test anywhere, though. I'm using this document to code my illegal opcodes and I've r...

So I've spent about 8 hours debugging now and I'm kind of stuck. I'm currently just trying to render the background before I move onto sprites, and everything looks like it *should* be working correctly in my code. The screen shows a different story, though. I'm using Donkey Kong as a test game and ...

Another question about rendering turned on/off. If background rendering is turned off, does the ppu still go through the attribute/nametable/tile fetch and all that, or does the ppu just idle and render pixels from whatever pallete value is at $3F00?

So I've gotten the background part of my ppu written and I'm trying to test it, but I'm failing miserably. I'm just trying to get one frame rendered at the very least. Right now, I'm not even reaching any of my PPU functions because $2000 stays 0x00 and $2001 stays 0x10. I know my CPU works because ...