Re: pnp

Pavel Machek (pavel@elf.ucw.cz)
Fri, 1 May 1998 11:00:47 +0200


Hi!

> > Unfortunatelly there is no standards for winmodem :-(( Only API-level
> > standards required for windows-driver... This means also that winmodems
> > are incompatible on hardware level :-((
>
> It's not quite that bad. With just two drivers, Linux could support most
> modems. Hardware vendors mostly buy chips and drivers from Rockwell,
> and they don't like writing drivers any more than we do.
>
> Some modem types:
>
> 1. Modems based on Rockwell's RPI chipset. These modems accept some
> standard AT commands for identification. The OS only needs to supply
> compression and error correction. (these are common)

This means that I can dial with ATDT with this modem, and it will
connect on 28.8k, but it will nor compress nor error correct?

> 2. U.S. Robotics WinModems, well-known for their lack of a normal UART.
> I'm fairly sure these are like RPI modems. (these are common)

> 3. IBM's MWave, maybe also used/developed by AT&T. The OS must swap
> DSP code in/out of the device as needed, but other than that it
> seems to be a normal modem. (these are found on IBM hardware)

For which of these are docs available?

> About that patent: the Linux drivers can just refuse to negotiate
> compression. It's useless for transferring gzipped files anyway and
> it adds latency.

Agree. Compression is not mandatory, we already have compression on
ppp layer. (I never tested it.)

-- 
I'm really pavel@atrey.karlin.mff.cuni.cz. 	   Pavel
Look at http://atrey.karlin.mff.cuni.cz/~pavel/ ;-).

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