bandy@well.UUCP (Andrew Scott Beals) (01/05/89)
We have a number of 2400 baud modems here and they all have a common
trait - they all get wedged from time to time and require a power-cycle
before they'll come to their senses.
Is there a modem company that makes a modem where the DTR line can reset
its internal processor (via the hardware RESET line, no software please)?
I believe that the reason the modems hang is because there are bugs in
the firmware and the processors either go into infinite loops or start
waiting for interrupts that never happen.
From asking a few Bay Areans, it seems that no-one knows of a company that
makes modems with DTR tied to the uProcessor's RESET pin [through an
opto-isolator, of course] and everyone that I've asked has come up with
my initial cheap'n'dirty solution: an array of BSR-type ["Plug'n'power"]
modules with a RS232-based controller from Radio Shack. Ugh. Yes, it would
work. Yes, it could be a big security problem [lost business rather than
lost files]. However, it's much better to be able to frob a line remotely
rather than having to call our operator at 6am [only hours after he finished
the weekly full dumps] and ask him to power-cycle a modem.
Responses by mail, please, and I'll summarize if there's interest.
--
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