[plug] Linux & Voice Modems

[shayne]

Yeah. The big problem with the winmodems is that rather then going
dsp->decoder->RS232 like all good
modems, the winmodems are just a DSP that feeds the waveform to the CPU via
the given bus.(ISA/USB/Whatever).
So the processor has to then emulate the brains of the modem in CPU... Think
bad mojo here, particularly if your
OS has unpredictable scheduling...ergo linux2.4 without low latency patch or
earlier.....
I believe there is at least a provisional lin-modem infrastructure out
there, but my understanding is it's not good
for mission-critical stuff.  USB win-modem... ick!
I strongly implore you to go for an external modem that talks via your comm
port.

Shayne.
----- Original Message -----
From: Craig Ringer <craig at postnewspapers.com.au>
To: <plug at plug.linux.org.au>
Sent: Monday, November 04, 2002 11:29 AM
Subject: Re: [plug] Linux & Voice Modems


> > Has anyone had any experience with Linux and Voice Modems, and can
> > recommend
> > good brands/models? Also, any I should steer clear of?
>
> USB modems are risky as the "usb win modem" is out in force.
> Read /usr/src/linux/Documentation/usb/acm.txt
> its a really good summary of "safe" modems and explains how to deal with
> USB modems.
>
> That said, I've got a serial 56k modem (being used as ADSL backup for
> _when_ telstra kill the service) I bought maybe 4 years ago, a no-name,
> and its worked perfectly from the word go with no troubles at all.
>
> A quick warning with 56k serial modems - not all of them still support
> the hayes AT command set properly (in so far as there is a "properly")
> and can be diffivult to get working without the windows drivers. Yeah,
> you heard me - windows drivers for a 56k serial modem. If you get a
> repuatble brand you should be safe, don't know how common the problem is
> but I've seen at least 1.
>
> Craig Ringer
>
>