If you want to check out an amazing example of what was being done by some Atari 8-bit programmers at the time, check out "Alternate Reality: The City", a Datas

If you want to check out an amazing example of what was being done by some Atari 8-bit programmers at the time, check out "Alternate Reality: The City", a Datasoft game by Philip Price released in 1985. He used some really novel techniques to create a game that was visually and musically impressive for the time and architecture. Some of the techniques he employed (from an interview on Atariage.com a couple years ago) >1. Knowledge of the names of registers was from magazine articles. I was self-taught for the most part. On the tricks with the hardware, that was just me thinking up what cool things I could do with the functionality of the hardware. Cycle counting to determine the position of the television electron beam, using a sliding window and emitting to the front and back of the current visual screen, using interrupts to change the color registers on each scan-line (combined with cycle counting and moving the player missiles to be at two places at once on the scan line),the 3D stuff, security, encryption, texture mapping, music driver, all self taught (no books).