Tunnel – CSD Configuration Parameters: “CSD_”

The parameters with the prefix “CSD_” are related to MTX-Tunnel configurations for telemetry scenarios for conventional GSM data calls.

MTXTunnel allows you to receive GSM data calls (CSD) in order to create a GSM-serial gateway. It also allows you to use both at the same time, giving priority to the GSM calls. This function is ideal for reading meters where you must be able to connect to an electrical meter through a GSM call and via GPRS to obtain continuous readings or readings in real time. Examples of typical energy operators are Endesa, Iberdrola etc.

CSD_enabled

Description: This allows you to either enable or disable GSM data calls. If you set this parameter to “on”, the modem will answer GSM data calls after the first ring, establishing a GSM-serial gateway. If at any point the modem answers a GSM data call when a GPRS-serial gateway is already established, the GPRS-serial gateway is “frozen” to make way for the GSM-serial gateway. Once the GSM call is over, the GPRS-serial gateway is re-connected and returns to its previous state.

Possible values:

• on, off
• Default Value: off

Additional notes:

• Look at the examples in this and this example for a better understanding of this parameter. Use the helpline iotsupport@mtxm2m.com if you need any extra help
• Remember that it is only possible to accept CSD calls in GPRS mode, so if you need to accept a CSD call in a 3G modem, you need to configure it to work in 2G mode with GPRS_mode: 2g

CSD_commPort

Description: If the parameter CSD_enabled is set to “on”, CSD_commPort allows you to specify if the serial port to use when receiving a GSM call is COM1 or COM2.

Parameter valid from version MTX-Tunnel v7.29.

Possible values:

• 1, 2, 3
• Default values: 1

Additional notes:

• It is true we could use the parameter MTX_invertedCom to choose the COM of a CSD call. However, this parameter is indispensable if we need to have a GPRS-Serie gateway via the COM1 and a GSM-Serie gateway via the COM2, for example, to control 2 different devices using a single modem
• Value 3 is special, since it redirects the CSD call to the MTX 2 serial ports. That meas it is possible, for instance, to connect 2 metering boxes to just one MTX modem.

CSD_allPhones

Description: With this parameter it is possible to configure if any telephone number is authorized to call the modem for a GSM call (CSD) or only the authorized telephone number can make  the call.

Possible values:

• on, off
• Default value: on (all phone numbers are authorized)

Additional notes:

• This parameter with value “on” means that all telephone numbers are authorized. Typical behaviour of any other GSM modem in the market
• This patameter with value “off” means that MTX-Tunnel only allows calls made from authorized telephone numbers, increasing the security of Communications. The authorized telephone numbers must be configured with the parameters CSD_validPhone1 … CSD_validPhone16
• If a call is received from a no-authorized telephone number, the modem simply hang up the call

CSD_validPhone1, CSD_validPhone2… CSD_validPhone16

Description: When the parameter CSD_allPhones is “off”, there parameters are for indicate the authorized telephone numbers for the reception of a GSM data call (CSD call). You can set up to 16 telephone numbers.

Possible values:

• A valid telephone number
• Default value: nothing

Additional notes:

• The only valid characters for the telephone numbers are the character “+” and “0” … “9”