
Modern timers are the LAPIC timer and the HPET (Linux did even resort to using the PMC registers). I've tested my machine and I don't have it. These hardware is gone, it's not present on modern systems.

Note: this second timer is also supported by many Intel chipsetsĠ048 RW EISA PIT2 counter 3 (Watchdog Timer)Ġ049 ? EISA 8254 timer 2, not used (counter 4)Ġ04A RW EISA PIT2 counter 5 (CPU speed control) PORT 0048-004B - EISA - PROGRAMMABLE INTERVAL TIMER 2 generates an NMI on time out.Ġ047 -W PIT control word register counter 3 (PS/2, EISA)īit 5-4 = 00 counter latch command counter 3 PORT 0044-0047 - Microchannel - PROGRAMMABLE INTERVAL TIMER 2 That watchdog timer is also obsolete, it was either a secondary PIT or a limited fourth channel of the primary PIT: -P00440047.

I don't think the NMIs are at fault here.Įxternal NMIs are obsolete, they are hard to route in an SMP system.
