cvs commit: src/sys/dev/puc pucdata.c

[Warner Losh]

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