//c modems at > 2400

[fishern3485@cobra.uni.edu]

I'd like to thank those of you who replied to my post requesting information
on high bps problems with the //c.

I also tried calling 1800-SOS-APPL and for the first time at that number
found a twit.  He did not ask me if I got fries with my computer, but
he DID know how to look up the "list of common problems" in his database,
and not finding mine, told me to call the manufacturer OF THE MODEM.
(repeated attemts to ask him who at Apple still knows what a //c looks
like lead him to circle back to the previous suggestion.  *argh*)

Ho joy.  I expect them to say something intelligent like "I've never
heard of a Macintosh IIc before..."  I've already been told that
the people that make ProTERM say //cowners need a special cable,
but I know that's also bull.  It's just plain *sad* when the users
know more about the damn things than the people who BUILT them.

It seems the considered opinion that the //c has a fundimental hardware
flaw in that the lines that prevent uncontrolled data flow are used
by the //c for other purposes, causing data from the modem to fill
the buffer, and then continue to flow, overflowing the computer's
buffer. (128 bytes if I recall correctly; if not that, then 256)

After examening the ROM, I think it may be possible to build a special
interrupt handler that can use the modem and printer ports in tandum
to control the flow. (using the printer's send line to transmit the
critical DTR signal necessary to stop the modem)

If anyone has detailed information on the protocol for setting up
ACIA interrupts, or information on making modem drivers for the //c,
please drop me a line.  If it's in hardcopy form, I'd be happy to
pay for photocopy and mailing costs.  Thanks all for your help!

-- 
Nathan Fisher
  FISHERN3485@COBRA.UNI.EDU