Re: [patch] recover lost ticks

Brian Gerst (bgerst@quark.vpplus.com)
Tue, 16 Mar 1999 06:34:35 -0500

Ingo Molnar wrote:
>
> On Mon, 15 Mar 1999, Vojtech Pavlik wrote:
>
> > Second - there is hardware that can't be fixed, and that needs to have
> > interrupts disabled for more than 10 ms to work. Yes, for example the MS
> > SideWinder 3D Pro joystick .... (during the initialization, and subsequent
> > re-initializations).
>
> could you explain why exactly it needs interrupts disabled for more than
> 10 ms?

The Sidewinder digital protocol is uglier than sin. It needs to poll
for a 100 KHz clock on the joystick port. The need for precision timing
is so critical that even ISA DMA or PCI bursts can make the read miss
clock cycles. It takes that long to read a whole packet in from the
joystick.

--


				Brian Gerst


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