Messages in this thread | | | Date | Tue, 16 Mar 1999 06:34:35 -0500 | From | Brian Gerst <> | Subject | Re: [patch] recover lost ticks |
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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.
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Brian Gerst
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