[ntp:questions] Re: Windows timekeeping

Richard B. Gilbert rgilbert88 at comcast.net
Mon Aug 7 13:10:30 UTC 2006

Paul.Croome at softwareag.com wrote:

> Bryan Henderson schrieb:
>>If anyone knows of a computer architecture besides ISA and stuff
>>designed to be compatible with it that has a HH:MM:SS hardware clock,
>>speak up, but all the other clocks I can think of maintain a single
>>counter, and it's up to the OS to derive from it UT HH:MM:SS or local
>>HH:MM:SS for use by humans.
> The Sun SPARCstation IPC used an STMicroelectronics M48T02 chip (or
> its equivalent predecessor) as its TOY clock. The data format is
> YY:MM:DD d hh:mm:ss ['d' is the day of the week in the range 1-7].
> I'd guess that other Sun models of that era used the same technology.
> Paul

Digital Equipment VAX and Alpha computers used the chip from a wrist 
watch as a TOY clock.  It kept seconds, minutes, hours, days and months 
but not years; the year was handled by storing the year on disk each 
time the clock was reset.  (If you didn't do a SET TIME or reboot your 
system at least once a year, it would boot up with the wrong year!)

It's an idea that makes sense; why "roll your own" when you can get one 
off the shelf for pennies.

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