APPLESOFT
Summary
Apple's Microsoft-derived BASIC with floating point support. Available as a ROM card (Applesoft II ROM) or loadable from cassette/disk. Integer BASIC and APPLESOFT differ in numerous small details — including character codes (Integer uses "negative ASCII" with high bit set; APPLESOFT uses "positive ASCII"). The Applesoft II ROM Card allows switching between ROM and RAM versions via a single CALL (CALL 54514 RAM→ROM, CALL 3314 ROM→RAM — covered in March 1979).
The Applesoft ampersand (&) feature allows BASIC programs to call user-supplied machine-language extensions — when Applesoft encounters & at the start of a statement, it executes JSR $3F5. Alan G. Hill's Ampersort exploits this for fast sorts. Apple's official documentation was sparse; Pi articles in 1979 (and Call-A.P.P.L.E. October–December 1978) were among the first widely-distributed write-ups.
How Pi has treated it
- 1979-02 — V01 N01 — APPLESOFT volunteer lead from founding meeting
- 1979-03 — V01 N02 — Crosby's Lissajous program; ROM/RAM toggle CALLs
- 1979-12 — V01 N11 — Alan G. Hill's Ampersort exploits the ampersand interface
Related
- Integer BASIC
- Ampersand Interface