The live state is written by whatever watches real hardware, on ITS clock:
a window polls its keyboard once a HOST frame, which is not a machine
frame. Read straight through, that made a pad whose value could change in
the middle of a machine frame - breaking the one promise the device makes,
that asking twice in a frame gives the same answer both times. The manual
said it could not happen and the code allowed it.
It also made recordings that were not of the flight. The recorder sampled
on a frame boundary and the program read whenever it read, so the two saw
different bytes. A replay of that is a DIFFERENT FLIGHT, faithfully
reproduced: it flew a lander off the top of the screen that had never gone
there, and every check said the replay was deterministic and re-recorded
as itself, because it was. Both were true and neither was the point.
So the live state is latched once a frame. What the machine reads and what
the recorder writes are now the same thing by construction rather than by
two clocks happening to agree. Real hardware latches a controller once a
frame for the same reason.
WHAT IS STILL NOT COVERED: the latch itself. Every recorded pad already
changes only on a frame, so the tests cannot tell a latched live pad from
an unlatched one - the case that went wrong is the one with a real hand on
a real controller, which is the case a headless suite has none of. Said
here rather than left to look tested.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW
AnachronautandClaude Opus 5
ee77d79780