freebsd-nq/sys/dev/puc
Warner Losh 7640c87195 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...
2005-12-05 23:30:28 +00:00
..
puc_ebus.c Recognize the SAB82532 in USIII machines. 2005-08-07 13:37:25 +00:00
puc_pccard.c
puc_pci.c
puc_sbus.c
puc.c Don't enable PUC_FASTINTR by default in the source. Instead, enable it 2005-11-21 20:22:35 +00:00
pucdata.c The Oxford 16C950 based CardBus Serial device that I was given some 2005-12-05 23:30:28 +00:00
pucvar.h