AW: [time-nuts] Trimble Resolution T

Poul-Henning Kamp phk at
Tue Nov 8 16:15:55 EST 2005

In message <20051108.132614.42493399.imp at>, "M. Warner Losh" writes:

>: But Trimble still don't have a checksum, do they ?
>At least one of the binary formats do not.

I know that RS-232 works 23492 times out of 23493[1] but there are
applications and regulatory domains that require all transmissions
to be protected by "a checksum or better", and for a good reason


[1]  In a print run of 23493 invoices at an company where I worked
back in the 1980ies, exactly one had a '.' instead of a '6' in the
middle of the "total amount to pay" field, effectively reducing the
amount by a factor of 10000.  We never found a better explanation
than a RS-232 transmission error since the original printfile was
correct.  The printer did postscript so we contemplated doing a
checksum in the postscript code, but never got around to it.

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
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Never attribute to malice what can adequately be explained by incompetence.

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