Date: Thu, 21 Mar 1996 02:56:36 -0700 (MST) From: Terry Lambert <terry@lambert.org> To: pst@shockwave.com (Paul Traina) Cc: hackers@FreeBSD.org Subject: Re: real time interrupts in FreeBSD? Message-ID: <199603210956.CAA29454@phaeton.artisoft.com> In-Reply-To: <199603210330.TAA12579@precipice.shockwave.com> from "Paul Traina" at Mar 20, 96 07:30:14 pm
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> I've got a need for a kernel driver to go to sleep for a number of MS > and then be awoken by an interrupt. Timing is critical, so I can't just > tsleep and get rescheduled later, and I don't have hardware of my own to > generate the interrupt. > > Therfore, I need to get a free CTC register, program it up, and have it > generate an interrupt that I can service in the device driver. > > Does anyone have any suggestions/ideas/help/pointers on how to do this. > I've never done this kind of stuff with PC hardware before, so I don't > even know where to start looking. Rewrite the timer code to provide reschedulable one-shots. This means moving the TOD clock (lbolt/HZ) to 64 or 128 and taking over the RT clock for use in the one-shot. The fix was first described in 1994 (by me) 8-). Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.
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