> 2.9.1 | CSD initialization

> This section comprises the subsections Description, Used AT Commands, Flow Chart, Hints and Example. To move to these subsections please use the Navigation Frame or the appropriate buttons on the toolbar.

> 2.9.1.1 | Description

> This chapter describes the basic settings recommended for handling CSD calls. Before making a CSD call be sure that flow control is enabled as described in Section 2.2.2. All other settings listed below are optional:

> • | AT+CSNS=4 enables calls received without bearer capability element to be accepted as data call. By default, incoming calls without bearer capability element are assumed to be voice, except for fax calls with fclass 1 or 2. These are assumend as fax calls.

> • | ATX determines whether the ME detects the presence of dial tone and busy signal. If ATX>0 the CONNECTresult code will include the transmission speed.

> • | Using the ATS0 command you can specify the number of rings before the ME automatically answers incoming data calls.

> Note that all types of Siemens modules support autoanswer mode at least for data and fax calls. Autoanswerability for other services is module specific, such as autoanswering voice calls or network initiated requests for GPRS PDP context activation. For details see [2].

> • | Using the ATS7 command you can specify the number of seconds the ME will wait for the completion of call setup when answering or originating a call.

> • | Using ATS10 you can set the time the ME remains connected after having indicated the absence of the data carrier.

> • | ATS18 enables extended call release reports indicated every time a fax or data call is released or fails to be established. This is useful especially for MT single numbering scheme calls or calls received from analog devices.

> • | With AT+CBST you can select the bearer service and the data rate to be used when data calls are originated. The default mode "non-transparent" cannot be changed. For incoming calls the settings of AT+CBST are not relevant.

> • | Use AT+CRC to enable or disable the extended format of result codes for incoming call indication. In the case of CSD calls AT+CRC=1 can be used to replace the factory default result code “RING” with the extended format “+CRING REL ASYNC” or “+CRING FAX”.

> • | Use AT+CR to enable or disable an intermediate result code to report information about the connection when a call is being answered. In a data connection this is the result code "+CR: REL ASYNC" which is presented before the CONNECT result code.

> • | If you need to change radio link protocol parameters use AT+CRLP.

> • | Except for AT+CSNS and AT+CRLP all above settings can be stored to the user profile with AT&W.

> • | You can select ATV0 to set the short format (numeric code) or ATV1 to set the long format (verbose code) of result codes. In case of using the command without parameter the value will be set to 0. A list of numeric and verbose result codes can be found in [2], chapter ATV.

> • | Some products support the command ATV\0 to choose whether or not the CONNECT result code shall include the RLP trailer. See example in Section 2.9.1.5. See ATV command in [2] to make sure if the command is supported.

> • | If supported by your product use the AT^SCFG command to make settings for the indication of URCs via the RING line when a call is received during data mode. See [2] to make sure if the command is supported.

> 2.9.1.2 | Used AT commands

> Command | Explanation
> AT\Qn | Flow control
> AT+CSNS | Single Numbering Scheme
> ATX | Set CONNECT result code format and call monitoring
> ATS0 | Set number of rings before automatically answering the call
> ATS7 | Set number of seconds to wait for connection completion
> ATS10 | Set disconnect delay after indicating the absence of data carrier
> ATS18 | Extended error report
> AT+CBST | Select bearer service type
> AT+CR | Service reporting control
> AT+CRLP | Select radio link protocol param. for orig. non-transparent data call
> AT&W | Store current configuration to user defined profile
> ATV | Set result code format mode
> AT\V | Set CONNECT result code format (not supported by all products)
> AT^SCFG | Extended configuration setting (not supported by all products)

> For further details about the commands see [2].

> 2.9.1.3 | Flow chart

> Figure 52: CSD initialization - part 1
> Figure 53: CSD initialization - part 2
> Figure 54: CSD initialization - part 3

> 2.9.1.4 | Hints

> • | Data capabilities can be used only if activated on the SIM card. To take advantage of voice, data and fax a separate phone number must be available for each service.

> • | Not all network providers support all data rates. So you may need to ask your provider to find out what services are available.

> • | Generally, only AT+CBST=0 (auto bauding) and AT+CBST = 7 (9600 bps, [V.110]) are supported and provide reliable performance. All other settings can be tried, but depending on the network problems may be encountered.

> 2.9.1.5 | Example

> ***************************************
> Comment: CSD initialization
> ***************************************
> ***************************************
> Comment: Enable hardware flow control.
> ***************************************
> Subscr 2 Send: AT\Q3
> Subscr 2 Receive: AT\Q3
> Subscr 2 Receive: OK
> ***************************************
> Comment: Set single numbering scheme to receive all calls without bearer elements as CSD call.
> ***************************************
> Subscr 2 Send: AT+CSNS=4
> Subscr 2 Receive: AT+CSNS=4
> Subscr 2 Receive: OK
> ***************************************
> Comment: Enable dial tone and busy detection.
> ***************************************
> Subscr 2 Send: ATX4
> Subscr 2 Receive: ATX4
> Subscr 2 Receive: OK
> ***************************************
> Comment: Enable automatic answer mode: answer after 3 rings.
> ***************************************
> Subscr 2 Send: ATS0=3
> Subscr 2 Receive: ATS0=3
> Subscr 2 Receive: OK
> ***************************************
> Comment: Set number of seconds to wait for connection completion to 60sec.
> ***************************************
> Subscr 2 Send: ATS7=60
> Subscr 2 Receive: ATS7=60
> Subscr 2 Receive: OK
> ***************************************
> Comment: Set waiting time after absence of data carrier before disconnect ME to 1 sec.
> ***************************************
> Subscr 2 Send: ATS10=10
> Subscr 2 Receive: ATS10=10
> Subscr 2 Receive: OK
> ***************************************
> Comment: Enable extended error report for CSD and FAX calls.
> ***************************************
> Subscr 2 Send: ATS18=1
> Subscr 2 Receive: ATS18=1
> Subscr 2 Receive: OK
> ***************************************
> Comment: URC indication in data mode via RING line (not supported by all products)
> ***************************************
> Subscr 1 Send: AT^SCFG="URC/Datamode/Ringline","on"
> Subscr 1 Receive: AT^SCFG="URC/Datamode/Ringline","on"
> Subscr 1 Receive: ^SCFG: "URC/Datamode/Ringline","on"
> Subscr 1 Receive:
> Subscr 1 Receive: OK
> ***************************************
> Comment: Set short result code format. Note that due to this setting the response OK will be replaced with the numeric code 0. See command ATV in [2] for a list of numeric and verbose result codes.
> ***************************************
> Subscr 2 Send: ATV0
> Subscr 2 Receive: ATV0
> 0
> ***************************************
> Comment: Select data rate to be used for mobile originated CSD calls (9600 bps V.32).
> ***************************************
> Subscr 2 Send: AT+CBST=7
> Subscr 2 Receive: AT+CBST=7
> 0
> ***************************************
> Comment: Disable service reporting control.
> ***************************************
> Subscr 2 Send: AT+CR=0
> Subscr 2 Receive: AT+CR=0
> 0
> ***************************************
> Comment: Set radio link protocol parameter.
> ***************************************
> Subscr 2 Send: AT+CRLP=61,61,78,6
> Subscr 2 Receive: AT+CRLP=61,61,78,6
> 0
> ***************************************
> Comment: Store settings to user profile.
> ***************************************
> Subscr 2 Send: AT&W
> Subscr 2 Receive: AT&W
> 0