Built this for a reinforcement learning project (PPO on Super Mario Bros), but the emulator side turned out to be the interesting part, so I figured this sub would care more about that.

One CUDA thread runs one entire console. 6502, PPU, bus, OAM DMA. State is structure-of-arrays indexed by env id, and CPU registers stay in hardware registers for the life of the kernel. 65,536 independent consoles at about 3.3M steps/s on an A100.

- CPU passes the Klaus functional test suite, cycle counts included

- PPU is not cycle accurate. SMB's title screen never advances past the menu because of a timing bug I haven't fixed. I sidestep it by resetting from a save state

- No APU. The registers exist as a byte array, nothing generates sound

- Mapper 0 only

Two results that surprised me:

Opcode-binned dispatch (sorting a warp's threads by opcode before executing) came out 3.2x slower than just letting them diverge. I tested it on instruction streams sampled from 535M profiled SMB executions. A decorrelated warp holds about 20.6 distinct opcodes, and hardware SIMT reconvergence was already sharing fetch and addressing acrossthem. Explicit binning serializes what it was already sharing.

Putting the zero page in shared memory was a 1.9x regression. 256 bytes across 128 threads is 32KB per block, which drops occupancy from 32 warps to 6.

https://github.com/hbofz/NeSLE

Would love help with mappers. MMC1 and MMC3 would open up most of the library.

Hello there everyone, this is my first of lets say many posts. I would like seek some guidance on how to get started on gameboy emulator. I worked on chip-8 and knocked that one out of the park. I mostly use C++ and Opengl but I am very agnostic when it comes to tech stack. I was hoping I could take the Chip-8 route of finding a relative readable specification that does not mercilessly bombard me with information but I have had no luck. I am sorry about being lazy and not taking the effort to find a good one in advance. Hope you have a good day!