Re: Linus... (or anyone) and timeloss in joystick driver.

Harald Koenig (koenig@tat.physik.uni-tuebingen.de)
27 Jun 95 00:31:45 MES


In <Pine.3.89.9506261225.D38155-0100000@werner.exp-math.uni-essen.de> Michael Weller <eowmob@exp-math.uni-essen.de> writes:

> Someone (whose name I accidently deleted) experienced a loss of 3.4 ms
> during a VC switch in his joystick driver.

> I don't think the loss of 3.4 ms is THAT important to the joystick driver.
> You trigger a new AD conversion and.. well you just read it back some
> time later. The program using the joystick should disable itself anyway
> if the console is switched away, so it really makes no difference.

3.4ms would be really *bad* for other operations too, e.g.:

one character at 38400 baud is 0.26 ms, so in 3.4ms one serial line
could receive ~13 characters! even with a 16550A uart with 16 byte FIFO
this might result in lost characters!

Harald

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