* [https://www.oxyron.de/html/registers.html Oxyron IC reference]
*[[Media:Altirra Hardware Reference Manual - 20240921.pdf|Altirra Hardware Reference Manual]] Latest (09/2024!) Atari XL hardware documentation
*[https://www.youtube.com/watch?v=lp4SFtRE0fQ&list=PLIX9fyYxV0k-vpin8ZBWzWe-wdPmS2j6e C64 vs Atari 800XL] [https://youtu.be/ioZRUVTKLx0 C64 SID vs Atari Pokey]
[[Category:Non CPC Computers]]