John Siracusa1d ago

“Apple II Forever” indeed…

https://www.inkandswitch.com/slow-software/

Show threadxot1d ago
@siracusa Yeah, that seems very wrong. Apple II should be about 8.3 ms on average, strictly based on the time it takes an NTSC signal to paint the CRT. The time it takes for a key press to put a character into display RAM is about 10 microseconds (10 cycles at 1.023 MHz).
Show threadxot
@siracusa Oops. I failed to consider the keyboard encoder circuit. So add 20 microseconds to latch the key, and a whopping 10 ms for the switch debounce circuit.
Apr 5 at 2:37pmWeb