[FSO/SHR-testing] Too much echo suppression?

Al Johnson openmoko at mazikeen.demon.co.uk
Thu Mar 12 13:53:00 CET 2009

On Thursday 12 March 2009, Vasco Névoa wrote:
> Hi all.
> I've been happily using SHR without any GSM call echo, but the callers
> do complain that they hear me badly.
> I've tried calling the Neo from a landline, and I think the Neo is
> chopping the sound, making it hard to understand. I don't think it is
> a problem of volume.
> I think this is probably the result of echo suppression/cancellation
> being set too strong...
> I'd like to experiment with various levels of echo processing; where
> do I find info about the available AT commands, and where in FSO do I
> have to tweak?

The AT commands appeared in this mail to the hardware list:
The descriptions are the string returned by the modem when the command is 
entered, and that's as much as we know. The numbers appear to make a bitmask, 
but the modem will only accept the numbers listed.

Look in /usr/lib/python2.x/site-
packages/framework/subsystems/ogsmd/modems/ti_calypso/channel.py where x will 
depend on whether your image is using python 2.5 or 2.6.

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