Date: Mon, 5 Dec 2005 23:30:29 +0000 (UTC) From: Warner Losh <imp@FreeBSD.org> To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org Subject: cvs commit: src/sys/dev/puc pucdata.c Message-ID: <200512052330.jB5NUTlW066532@repoman.freebsd.org>
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imp 2005-12-05 23:30:29 UTC
FreeBSD src repository
Modified files:
sys/dev/puc pucdata.c
Log:
The Oxford 16C950 based CardBus Serial device that I was given some
time ago appears to be based not on the typical 1.8432MHz clock, or
the other more typical multiple of 8 of this (14.7456MHz), but instead
it appears to be 1/2 the PCI clock rate or 16.50000MHz. I'm not 100%
sure that this is right, but since I did the original entry, I'm going
to go ahead and modify it. With the 14.7456MHz value, I was getting
bits that were ~7.3us instead of ~8.6us like they are supposed to be.
My measuring gear for today is a stupid handheld scope with two
signficant digits. So I don't know if it is 33.000000/2 MHz or some
other value close to 16.5MHz, but 16.5MHz works well enough for me to
use a couple of different devices at 115200 baud, and is a nice even
multiple of a well known clock frequency...
Revision Changes Path
1.53 +2 -1 src/sys/dev/puc/pucdata.c
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