[ntp:questions] Re: Bought a GPS receiver--What next?

Wolfgang S. Rupprecht wolfgang+gnus20041101T225542 at dailyplanet.dontspam.wsrcc.com
Tue Nov 2 07:09:32 UTC 2004

"Richard B. Gilbert" <rgilbert88 at comcast.net> writes:
> How would you transfer that 64bit time value?  How would you control
> the timeing of the transfer?  Very few computers have 64bit parallel
> interfaces!!!!

The up and coming buses are all essentially serial.  Hypertransport is
just an single line clocked at 800Mhz (or a touch more).  You send a
command down one wire and the other side sends a reply.  You can
certainly ask for more than a byte at a time.  This isn't something
that only fast/expensive cpu's use.  Even slow/cheap cpu's like the
Transmeta are starting to use it, simply because it cuts down on pin
and wires.


In any case, even a 64-bit/128-bit linear time-keeping register read
8-bits at a time would be just fine.  One would latch the count, and
then read all the bytes.  This more or less what one does any time one
reads a multibyte value from any byte-accessible chip used in
computers.  (Or am I answering the wrong question?  Sorry if I'm not
correctly following what you are asking.)

Wolfgang S. Rupprecht                http://www.wsrcc.com/wolfgang/

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