>> There are no errors. A connected modem works fine. However, this
>> is a long-used call-back program which runs fine at speeds at and
>> below 38400. However when I set the speed to higher values, I
>> noted that the modem would only connect at 1200 baud!
> Well, I can't duplicate it on my 2.2.0-pre7 machine, with RedHat 5.2,
> and glibc 2.0.7.
I have seen the described behaviour in the past, and the problem was
modem-specific...
In my case, it was a Pace Supreme 14k4 FaxModem, and the modem
firmware had a bug in it where if the serial baud rate was higher than
38,400 Baud, it would quite happily talk across the serial link at
whatever speed was set, but would only allow the modem to connect at
speeds up to 4,800 Baud - yes, it would connect at 4,800 Baud (which
uses the 9,600 Baud signalling method) but not at 9,600 Baud.
I proved this by trying different modems - with that Pace being an
external modem (yes, the PC had a 16550AF uart), that wasn't hard. An
external USR Sportster 14k4/VoiceFax and an external BT 14k4 modem
both worked perfectly if the serial baud rate didn't exceed 57,600,
which is all they're specified up to - neither would even see the
text sent over the serial port at 115,200 Baud.
At the time, I wasn't on the Internet, but I wrote to Pace about this,
and received a note thanking me for the information, but not otherwise
commenting...
Hopefully, that helps...
Best wishes from Riley.
--- * ftp://ftp.MemAlpha.cx/pub/rhw/Linux * http://www.MemAlpha.cx/~rhw/kernel.versions.html
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