lucent modem ? where it is ?

[Gary Corcoran]

Mark Santcroos wrote:
> 
> On Sun, Jul 06, 2003 at 03:48:40PM -0400, Gary Corcoran wrote:
> > Seems you got a "soft modem", which really isn't a modem, but
> > only a codec (analog-to-digital and digital-to-analog converters).
> > The rest is done by (windows) software.  Your Pentium is responsible
> > for doing all the work that the DSP of a regular modem does, and so
> > you don't just need a "driver" in the usual sense.  Which is why the
> > normal Lucent driver won't work, and why you can't just "get specs"
> > to drive it.  In other words, the "driver" has to contain full
> > Digital Signal Processing code (plus the usual driver code) to
> > send/receive all the complex audio tones that a modem handles (in
> > real-time, of course).  This is so the manufacturer could save a
> > couple of dollars (instead of buying the real modem chip)...
> 
> Your story is true, but doesn't really address the issue.
> 
> What was meant by "the Lucent driver" (see ports/comms/ltmdm) is a driver
> for (some of) the ISA/PCI type Lucent softmodems.

Um, no, as far as I know, there is only the ltmdm driver for the Lucent
"winmodem"s, NOT the "softmodem"s.  There is a huge difference.  Winmodems
are only missing the "controller" CPU, so its functions are handled by
the ltmdm driver.  The ltmdm driver does NOT do the DSP functions, they
are handled by the ISA/PCI modem chips.

> It is not suited for this type of system (AMR/AC97) (yet).
> Whether the same driver could be made suitable easily is something I don't
> know without looking more at it. (Depends on whether it is the same codec
> probably)

Gary