Connection settings for connection between ISDN and GSM terminal

FAQ #100370

 

Reason
Since the ISDN TA is communicating using the bearer service V.110, the GSM terminal is to be configured to use this service, too. This configuration is done by editing the init string of the GSM.
Please note that also the ISDN TA must use the bearer service type V.110! Make sure this is the case (other common bearer service types such as V.120 are not supported by the GSM terminal MC35).

Procedure
The initialisation string of the GSM terminal is to be configured in the Hardware Settings of the PCD. In the "modem" tab of the HW settings, the init string is to be modified. The command "CBST=71,0,1" is to be introduced into the init string of the GSM terminals.

Example
The init string below sets a GSM terminal MC35 into auto answer mode (S0=2) and configures the terminal to use the bearer service V.110 (+CBST=71,0,1).
After the delimiter (semicolon), the command &W causes the modem to store the just entered configuration into flash. Therefore this configuration stays active until the bearer service is changed again (by the use of the command CBST). The reset string ATZ will not restore the default bearer service! 
The expression "\r" doesn't belong to the init string but serves as "End Of String" for the PCD firmware.
ATS0=2+CBST=71,0,1;&W\r

The +CBST command :
The table below shows the supported bearer service types as well as the syntax of the command.
Syntax:                   AT+CBST=<speed>[,<name>[,<ce>]]