{ "_comment": "Corrections to earlier annotations of the modem driver, found while specifying the SwiftLink replacement and verified against the opcodes.", "notes": { "E778": {"unit": "game/modemDriverE000", "line": "and clear the packet-layer send enable $E0A6 - NOT the only write to it: sendPacketFsm sets it at $E265 with 'sta uartPendingCount,x', X = inFlightSlotIndex = 1"}, "E8A3": {"unit": "game/modemDriverE000", "line": "packet-layer send enable; sendPacketFsm does set it (indexed, at $E265), so the code below IS reachable"}, "E6AB": {"unit": "game/modemDriverE000", "line": "$09 = START | one-shot - this does not stop timer B, and bit 4 (force load) is clear"}, "E6AD": {"unit": "game/modemDriverE000", "line": "run exactly one more bit period, the stop bit, after which the CIA clears START itself; that final underflow drives txBitCounter negative into nmiStartNextChar, which is how characters chain back to back without waiting for the frame tick"} } }