This page is to serve as a backup of some of the NES Programming documentation floating around the intertubes. Most of it requires you to know a bit about ASM already. It is recommended you start with Nerdy Nights.

nestech.txt (Y0SHi)

NESprogam.zip Programming the 8Bit beast of Power, the NES. By joker21@earthlink.net

NESDoc.pdf Very Detailed Documentation, by Patrick Diskin

nesdev.zip Web-browser based tutorials, by cr_3xs@hotmail.com

NES6502.txt ASM Tutorial by GBAguy, written when he was 15. Updated at http://www.patater.com/nes-asm-tutorials

NES101.zip Okay if you know ASM already.

NES_Stuff.zip Contains nestech.txt, NES ASM 6502.txt and Mappers.txt (different authors)

NES Programming Guide.txt by Bokudono. 

emuprog.pdf Study of the Techniques for emulation programming, by Victor Moya del Barrio. This document is good if you want to make an emulator from scratch.