Integer BASIC
Summary
The original BASIC of the Apple II, designed by Steve Wozniak and built into ROM. Restricted to integer values (no floating point in language itself, but the Monitor has FP routines). Memory layout uses HIMEM ($4C/$4D), PP / Program Pointer ($CA/$CB), LOMEM ($4A/$4B), PV / Variable Pointer ($CC/$CD).
Pi-relevant gaps and workarounds covered in 1979:
- No CHR$ — Jim Rose documented a POKE 2053, … workaround using a single-letter string variable
- No way to call ML routines with register values — John L. Moon built a POKE-and-CALL interface
- No floating point arithmetic directly accessible — Moon's interface to the Monitor's FP routines
- No directly-callable hex print — Moon walked through using JSR $F940
How Pi has treated it
- 1979-02 — V01 N01 — iBASIC training as a founding goal; Sandy Greenfarb volunteer
- 1979-03 — V01 N02 — iBASIC vs APPLESOFT agenda item
- 1979-04 — V01 N03 — Jim Rose's CHR$ workaround
- 1979-05 — V01 N04 — Moon's "Locating Integer BASIC Variables" and "Floating Point in Integer BASIC"
- 1979-09 — V01 N08 — Greenfarb's "Internal Structure of Integer BASIC" (reference)
Related
- APPLESOFT
- 6502 Machine Language
- Floating Point Arithmetic