Linux and similar use the PC "watchdog timer". This is on the NMI PIT
(timer). This is a very poor use of the hardware's highest priority
interrupt. I'll be using the NMI PIT for hard realtime services. This is
also simpler and perhaps faster than rtlinux and similar. What we lose is
the ability to "gracefully" turn off a toasted machine. BFD. This is how
the suits at IBM snowjobbed over thier general lack of rhythm. In other
words, IBM took the ebusiness infrastructure of the world level of
conservatism to the design of the PC, which is why they never should have
gotten into PCs. The PC AT is fundamentally clocks-challenged, but using
NMI PIT for realtime should help.

There may be PCI clocks you can assume nowadays, dono.


