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Entry type: FAQ Entry ID: 29586028, Entry date: 10/15/2008

How do you parameterize the GSM modem MD720-3 for use with SINAUT ST7?

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  • Associated product(s)
From firmware version V1.7.3 onwards, modem MD720-3 can be used as a GSM dial-up modem for SINAUT ST7. It is not possible to upgrade modems with older versions of the firmware.

You need the following components to use the GSM modem MD720-3 with SINAUT ST7:

  • TIM with the following firmware version:
    - TIM3 / TIM4 without Ethernet port: firmware version V4.3 or higher.
    - TIMxx-IE with Ethernet port: firmware version V1.0 or higher.
  • Plug-in connecting cable:
    standard plug-in connecting cable, order number 6NH7701-5AN. (can also be used for connecting the MC45T, TC35T, M1 and M20T modules).
  • SIM card:
    the SIM card must be enabled for data transfer. More information on this is available in Entry ID 24073197. At startup, the TIM checks whether the card is enabled. If the SIM card is not enabled for data transfer, the TIM enters a relevant error message in your diagnostics buffer.

Make the following settings in NetPro.

  1. Double-click on the TIM. A window with the TIM properties opens. Switch to the "Interfaces" tab. Click on the WAN interface to which you want to connect the MD720-3. Then you select "dial-up network" as the network type (see Fig. 1).

    Fig. 1

  2. Click on "New..." to create the network node and then on "Properties" to parameterize the node. A window opens as in Fig. 2.

    Fig. 2

  3. Make the following settings regardless of the partner modem and baud rate in the GSM network.

    Click on "New..." in the window as shown in Fig. 2 in order to create the SINAUT dial-up network. The following window opens (Fig. 3). Set the "Baud rate", "Message format" and "Retry factor" parameters as shown in Fig. 3 and confirm with "OK".


    Fig. 3

  4. In the window of Fig. 2 that is still open, switch to the "Basic Parameters" tab. Set the "Operating mode" and "Extra transmission time" parameters as shown in Fig. 4 and confirm with "OK".

    Fig. 4

  5. In the window still open with the TIM properties, you can now select the modem type. Select "TC35T /MC45/ MD720-3" for the modem type.

    Fig. 5

  6. If your version of the SINAUT configuration tool does not yet provide the option "TC35T /MC45/ MD720-3", select "TC35T/ MC 45".

    After making this setting, it is possible to set the dialing parameters. Click on "Properties". A window with the network node settings opens. Switch to the "Dialing Parameters" tab to enter the telephone number and PIN of the SIM card.

    Fig. 6

    If the PIN is incorrect, the MD720-3 returns an error message to the TIM. The TIM then generates a diagnostics message and stops communication with the MD720-3. This procedure avoids the SIM card from being locked by repeated transfer of an incorrect PIN. Furthermore, the TIM checks the PIN in the MD720-3 every 30 minutes. If the PIN is no longer available (e.g. due to a restart of the MD720-3), the TIM transfers the PIN again.

  7. Switch to the "AT Initialization" tab. If the AT strings are not already preset, check the option "User defined", parameterize the AT strings as shown in Fig. 7 and confirm all the windows with "OK".

    Fig. 7
    The procedure for parameterizing the partner modem is identical except for the AT strings. Table 1 shows the values to enter depending on the modem.

Partner modem AT strings for the MD720-3 and the partner modem
MD720-3 For MD720-3:
For MD720-3 of partner:
MD4 For MD720-3:
For MD4 of partner:
MD3 For MD720-3:
For MD3 of partner:

Table 1

1) The x stands for the MSN that the SINAUT configuration tool enters automatically.

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