Atari 2600 / F209
BEING VERIFIEDIMPLICIT ALU ADDRESSING NEEDS ENCODED WIDTH
- STATUS
- BEING VERIFIED
- AREA
- Recompiler
- RECORDED
- 2026-07-15
- PUBLIC SOURCE
- Research dossier / finding 209
- RECORD ID
atari2600-f209- SNAPSHOT
d8dcf6d8dd492341
HYPOTHESIS: all eight official ORA modes compute their effective address with the addressing mode encoded by the opcode, OR the fetched byte into A, and set only N/Z from the result. In particular, absolute-indexed $00xx remains a three-byte absolute address and may carry into page $01; it is not a zero-page-indexed alias.
Raw traces, ROM material, local paths, and personal data are not part of this public record.
01INPUT IDhash receipt
02BYTE MAPdecode coverage
03CPU STATEtrace comparison
04BUS / TIMEordered effects
05OUTPUTvisual · audio · input
06ARTIFACTbuild identity