User`s guide

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SIM card PIN code
The PIN code is used to check authority to the SIM card. A PIN code is
assigned by the GSM operator. Place the SIM card in a mobile phone if you
want to change it.
Network ID
The ID of the GSM network that issued the SIM card used in the GSM
module. Press F4 to display a window with available networks.
Service centre address to use
Service centre address to use when sending messages through this
configuration.
1=Sender The service centre address of the SIM card in the GSM
module will be used.
2=Receiver The service centre address for the receiver's network defined
in the network file will be used.