Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 11 Jun 2003 02:13:04 -0400
From:      Gary Corcoran <garycor@comcast.net>
To:        Andy Sparrow <spadger@best.com>
Cc:        freebsd-mobile@freebsd.org
Subject:   Re: FreeBSD laptop with: 56k modem, ethernet, Xfree86
Message-ID:  <3EE6C870.FB1A7FE7@comcast.net>
References:  <20030611035011.54DBF1E0@CRWdog.demon.co.uk>

next in thread | previous in thread | raw e-mail | index | archive | help

Andy Sparrow wrote:
> 
> Ironically enough, although they no longer ship a Lucent modem, IBM used
> to,
...
> and the ltmdm  port works fine[0].
<snip>

> [0] This superb piece of work is actually a loader that loads a software
> image into the modem and then "talks" to it for you, if I understand
> correctly - it's more like a "softmodem" than a "winmodem". CPU load is
> not noticably increased at all with a PIII-600.

You have your terminology backwards.  A "softmodem" is when the realtime
DSP functions are performed on your CPU, taking a good chunk of it.
The "ltmodems" are so-called "winmodems", where the CPU just takes the
place of the "controller", which handles things like interpreting the
"AT" commands, and was typically something like a little Z-80 microprocessor
(remember those? :) on-chip.  So you can see that it takes next-to-nothing
of a modern Pentium CPU to handle that, which is why you don't notice any
increase in load with a "ltmodem"...

Gary



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?3EE6C870.FB1A7FE7>