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Re: [lwip-users] hayes commands popping up in ppp stream
From: |
Sergio R. Caprile |
Subject: |
Re: [lwip-users] hayes commands popping up in ppp stream |
Date: |
Fri, 14 Nov 2014 10:11:01 -0300 |
User-agent: |
Mozilla/5.0 (Windows NT 5.1; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 |
BTW,
"\r\nUNDER-VOLTAGE WARNING\r\n"
is a clear indication that your power supply is not well designed and/or
your module is not well decoupled.
It needs >2A current to transmit for a very short time, you need a 100uF
low impedance
in parallel with 2uF MLCC close to the module; or better, what the
hardware manual recommends.
And make sure your power supply can provide that current for that amount
of time,
which you'll find in the manual.
Sorry about that, but I used to work with the tech support for Simcom in
Argentina...
On 14/11/2014 10:06 a.m., Sergio R. Caprile wrote:
> My view:
> Since PPP expects a serial transparent interface, and you are not
> providing that, I would write a "tap" which provides that to PPP and
> "taps" all other data out.
>
> GSM modem ----> real serial --> my module -----> PPP virtual serial
>
> -----------> tracking virtual serial
>
> Some GSM modems provide a packetization interface to clearly separate
> muxed channels on the same serial interface. If yours does not, you'll
> have to work harder.
>
>
--
-------------------------------------------------
Sergio R. Caprile, Human Being, Bs.As., Argentina
Electronics Engineer, Musician (guitarist), TaoFx
http://www.scaprile.ldir.com.ar/
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