WISMO0228 - CSD Call


I have an issue in getting a CSD call working with WISMO0228 module.
Voice call ( ATDNNNNNNN; ) works without any issues.

When I try to make a CSD call ( ATDNNNNNNNN ) module responds with “NO CARRIER”
I have checked AT+CGCLASS. It was in “B”, I tried changing it to “CC”. Still it gives the same result.

The CSD call with the same SIM card with another modem works.

Appreciate any hints to sort this out…


Did you try


It does not work.

AT+CGCLASS sets the GPRS Mobile Station Class

Use AT+CBST to set the Bearer type for CSD

use AT+CEER to get the Clearing Cause immesiately after the call ends.

Post the exact command sequence you are using - and the responses.

Hi Please find attached commands and response.

AT+CEER gives “Cause Select:67 Cause:57”

What could be the issue ?

I tried with another SIM card.
AT+CEER gives “Cause Select:67 Cause:31”


Any help ?

Have you tried looking up those codes?

Failure Cause from 3GPP TS 24.008 says the following

Cause :57 = Bearer capability not authorized
Cause :31 = Normal, unspecified

but no idea what it means !

“Bearer capability not authorized” means that the type of call is not allowed - so you’re going to have to ask your service provider what type(s) of CSD calls are supported.

Are you sure that they support CSD at all - it is a dying service…

“Normal, unspecified” is just a standard call hangup.


I tried with another SIM, and it works.
Looks like I need to enable CSD from the service provider.
Is there any AT command which can list all the present settings from WISMO0228 ?


Or you need to correctly configure the modem for the service(s) provided

Again, look at the AT+CBST command…