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Re: The continuing saga of my 5000/200 [was Re: DECstation 5000/200 timekeeping]



[Replying to content scraped from mail-index, hence suboptimal threading]

> [[ sun4c does not show ~10-sec-per-min drift seen on DECstation 5000/200 ]]

> Thanks very much!  Can you confirm that there are no timecounter
> sources on either machine, except for the RTC?

On the 5000/300, yes.  As I wrote on 2021-10-26, I saw

kern.clockrate: tick = 3906, tickadj = 15, hz = 256, profhz = 256, stathz = 256

kern.timecounter.choice = clockinterrupt(q=0, f=256 Hz) dummy(q=-1000000, f=1000000 Hz)
kern.timecounter.hardware = clockinterrupt

On the SS2, I forgot to check that at the time.  I just now booted that
setup again (I haven't had occasion to write to that disk since) and I
see

kern.clockrate: tick = 10000, tickadj = 40, hz = 100, profhz = 100, stathz = 100

kern.timecounter.choice = clockinterrupt(q=0, f=100 Hz) timer-counter(q=100, f=1000000 Hz) dummy(q=-1000000, f=1000000 Hz)
kern.timecounter.hardware = timer-counter
kern.timecounter.timestepwarnings = 0

dmesg includes

timer0 at mainbus0 ioaddr 0xf3000000 ipl 10: delay constant 17, frequency = 1000000 Hz
timecounter: Timecounter "timer-counter" frequency 1000000 Hz quality 100

and sys/arch/sparc/sparc/timer.c (timer_get_timecount) looks, at a
quick glance, as though it's accessing some kind of free-running
counter hardware.

I'll see if I can dig up other sun4c (SS1 or SS1+, most likely) to see
what they have.

> i'm currently not well,

Oh, that's not good to hear.  Here's hoping you get better soon and
thoroughly!

> but i'll look into this as and when I can.

Thank you!  But, please, take care of yourself first.


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