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I have problem with call auto answer in modem Huawei E303.

On modems E173 auto call anwer is working fine. But on Huawei E303 it's not working.

Steps that i do: Open kermit:

set line /dev/ttyUSB0
set carrier-watch off

then i type AT command for answer on first ring:


and when i'm calling on that modem nothing happens. So question is is there something that can be done to make it auto answer or it's a hardware restriction ? i know that on E303 voice is enabled, and i can make call with it by typing ATDT XX_MY_NUMBER;

EDIT: So when i'm calling on that modem i dont see anything in output but if i type in console force answer call at command:


that modem answers the call. So call answering is enabled, but why still ATS0=1 isn't working ?

EDIT2 So I made some debugging with kermit application and ran command: SHOW COMMUNICATIONS

E303 modem returned output: ( modem that does not auto answers on call)

 Carrier Detect      (CD):  Off
 Dataset Ready       (DSR): On
 Clear To Send       (CTS): On
 Ring Indicator      (RI):  Off
 Data Terminal Ready (DTR): On
 Request To Send     (RTS): On

And my E173 modem that is auto answering calls:

 Carrier Detect      (CD):  On
 Dataset Ready       (DSR): On
 Clear To Send       (CTS): On
 Ring Indicator      (RI):  Off
 Data Terminal Ready (DTR): On
 Request To Send     (RTS): On

Other commands like "SHOW MODEM", and "SHOW DIAL" returns same equal output, so only difference is with Carrier Detect (CD): On / Off

So can it be the problem why E303 modem does not make auto call answering if at command ATS0=1 was given ?

share|improve this question
Do you get RINGING on the terminal when you call the modem? – Flup Mar 18 '13 at 12:20
No, and I newer seen that answer command on any of huawei modems using kermit or putty on windows. When i call to that modem i hear tones, but on other models of huawei I get answer after first tone. – user777 Mar 18 '13 at 12:28

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