isat ???

[karn@ka9q.bellcore.com (Phil Karn)]

The "isat" command specifies whether the system has the Intel 8254 timer
chip used in the AT and later model PCs and PC clones. This is distinguished
from the 8253 chip used on the original PC and the XT.

I recently enhanced the timer routines to get resolution better than one
tick, but I could only make it work on the 8254 chip. Unfortunately there
seemed to be no easy way to tell the difference between the two chips in
software, so I punted the issue and left it a configuration option.

Phil