REFORGE
Atari 2600 / F228
BEING VERIFIED

ROL MUST SNAPSHOT OLD CARRY BEFORE WRITING NEW CARRY

STATUS
BEING VERIFIED
AREA
Recompiler
RECORDED
2026-07-15
PUBLIC SOURCE
Research dossier / finding 228
RECORD ID
atari2600-f228
SNAPSHOT
d8dcf6d8dd492341

HYPOTHESIS: ROL copies old carry into result bit 0, copies old operand bit 7 to new carry, masks to one byte, and derives N/Z from the result. Those two carry roles cannot share a mutable carrier without preserving their order.

Raw traces, ROM material, local paths, and personal data are not part of this public record.