- iNES: https://wiki.nesdev.com/w/index.php/INES
- https://medium.com/@fogleman/i-made-an-nes-emulator-here-s-what-i-learned-about-the-original-nintendo-2e078c9b28fe
- http://emulator101.com/
testrom/cpu_exec_space/test_cpu_exec_space_ppuio.nes testrom/nes_instr_test/rom_singles/10-stack.nes