#official
- Commodore 64 Programmer's Reference Guide publicationThe official Commodore / Howard W. Sams manual for the commodore-64 (1982). For music its parts are chapter 4 , "Programming Sound and Music on Your Commodore 64" (pages 183–208: introduction, volume control, …
- C64 Programmer's Reference Guide, ch. 4 — Programming Sound and Music on Your Commodore 64 (1982) summaryThe official 1982 introduction to the sid from the BASIC programmer's side: ten example programs that POKE the chip's registers, each with a line-by-line explanation, plus a short "technical explanation" of frequency, …
- MOS 6581 Sound Interface Device (SID) datasheet — the text behind Appendix O summaryThe manufacturer's twelve-page specification of the sid : block description, the 29-register map, a paragraph per register bit, the envelope rate table, the filter, pins and electrical data, the note table with a …