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Put a reset button on the case, and stop Escape closing the window

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ESCAPE WAS A BUG I LEFT. This machine sends Escape to the console like any other key, and
Raylib closes a window on Escape unless it is told not to - so a program reading keys could
be ended by one of them, taking whatever was in memory with it. SetExitKey(KEY_NULL), and it
is a byte again.

F12 is the reset button. A button on the case rather than a key the machine can see: nothing
sends a function key to the console, so nothing can be surprised by one. It does what writing
MACHINE_RESET does, which is that the machine starts the way it started - the boot chain runs
again and finds whatever the disk now says to run.

Which is what makes a bare metal program escapable. Once puts a demo in front of the next
start and deletes the request before jumping, so a demo that has taken the whole machine is
one keypress from the system coming back, instead of closing the window and opening it again.

IT HAD TO REACH A MACHINE THAT IS WAITING, and that took two more things. A reset is acted on
between instructions, and a machine blocked on a key is part way through one - so the button
would have set a flag that nothing ever came along to notice, in exactly the situation a
reset button is for. The wait ends now: the console is told its input is over, which it is
for a machine about to stop existing.

And the reset puts the console's input back - nothing pushed back, no line half gathered, and
not at the end of input. That was already wrong before the button existed: a reset after the
input ran out left a console that had run out afterwards, so a machine could be restarted
once and then never typed at again.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW
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Anachronaut
2026-08-29 11:05:16 -04:00
co-authored by Claude Opus 5
parent 13b20c8834
commit f7657081be
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@@ -47,6 +47,21 @@ The suite holds the two to being the same machine rather than taking it on trust
the entire manifest through Voyager as well, with `--headless`, and requires it to satisfy
every recorded result byte for byte.
**F12 is the reset button**, and it is a button on the case rather than a key the machine
can see: nothing sends a function key to the console, so nothing can be surprised by one. It
does exactly what writing to the machine port does - the machine starts the way it started,
which means the boot chain runs again and finds whatever the disk now says to run.
That is what makes a bare metal program escapable. `Once` puts one in front of the next start
and deletes the request before jumping, so a demo that has taken the whole machine is one
keypress away from the system coming back, without closing the window and opening it again.
It works on a machine that is stuck waiting for a key, too, which is when a reset button
earns its keep.
**Escape reaches the machine.** Raylib closes a window on Escape unless it is told not to,
and this machine sends Escape to the console like any other key - so a program reading keys
could be ended by one of them, taking whatever was in memory with it.
**The screen belongs to the machine, not to the window.** The video device is a tile engine
on ports 0x30 to 0x3F that brings its own bank of video memory, and it renders into a buffer
that is a pure function of that memory - so the same program draws the same picture whether