Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 22 Mar 1995 16:10:18 +1000
From:      Bruce Evans <bde@zeta.org.au>
To:        davidg@freefall.cdrom.com, rgrimes@gndrsh.aac.dev.com
Cc:        CVS-commiters@freefall.cdrom.com, cvs-sys@freefall.cdrom.com
Subject:   Re: cvs commit: src/sys/i386/isa wd.c wdreg.h
Message-ID:  <199503220610.QAA04588@godzilla.zeta.org.au>

next in thread | raw e-mail | index | archive | help
>>   Correct delay to use port 0x84, reading the status register
>>   might not be a long enough delay.

>Port 0x84 will not cause the 1.25uS delay on some PCI motherboards,
>I beleive all Intel Neptune and Triton based boards know that this
>is not an ISA address and end up running only a PCI I/O cycle for
>it.

What are the cycle timings for all PC buses?

ISA: 6 min + normally 4 extra = 1.25uS at 8MHz ?
EISA?
PCI?

Bruce



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199503220610.QAA04588>