> AT
OK


> AT+CFUN?
+CFUN: 1


> AT+CFUN=1
+CPIN: READY
OK
SMS Ready
Call Ready


> AT+CPIN?
+CPIN: READY
OK


> AT+COPS=?
+COPS: (1,"D1","TMO D","26201"),(2,"vodafone","voda D2","26202"),(1,"E-Plus","E-Plus","26203"),,(0-4),(0-2)
OK


> AT+COPS=0,0
OK


> AT+COPS=4,2,"26202"
OK


> AT+COPS=1,2,"26201"
OK


> AT+COPS?
+COPS: 1,2,"26201"
OK


> AT+COPS=3,0
OK


> AT+COPS?
+COPS: 1,0,"D1"
OK

Preperation

For testing purposes, connect the SIM800L (1418B05SIM800L24) to a computer. The commands used in this guide will be issued via the serial interface towards the modem. Please setup the specific hardware device that these AT Commands can be sent to the device serial interface. Further ensure that the 1NCE SIM is inserted correctly into the device.

Check Module Communication

Check that the module response to a basic 'AT' command. The device should return 'OK' as answer.

Check Functionality

Use 'AT+CFUN?' to check the functionality setting of the modem. '+CFUN: 1' should be returned, indicating that the modem is in the full operating mode.

Activate Functionality

If the prior command returns '+CFUN: 0', use 'AT+CFUN=1' to activate the full modem functionality.

Check SIM PIN

Use 'AT+CPIN?' to check if the SIM is ready to use. As the 1NCE SIM do not have a PIN set by default the modem should return '+CPIN: READY'.

If an error is returned, please check the SIM is inserted correctly or try the SIM in a smartphone.

PLMN Query

Use 'AT+COPS=?' to query all Public Land Mobile Networks that can be received with the SIM800L at the given location. Note this scan for operators can take some time to respond. In the returned result, all avaliable network operators are listed with the long, short an numeric identifiers.

PLMN Automatic Selection

To let the SIM800L automatically choose which operator to connect to, issue 'AT+COPS=0,0'. This sets the registration process to automatic.

PLMN Manual/Automatic Selection

Manual operator selection with a fallback to automatic is a good choice to ensure automatic failover in case of an outage. With 'AT+COPS=4,2,"26202"', manual/automatic mode (4) is selected and the numeric identifier setting (2) is used to set operator (26202). The numeric id of the operator needs to be set based on the preferred network from 'AT+COPS=?'.

PLMN Manual Selection

Manual operator selection without a fallback to automatic is generally not recommended due to the missing failover in case of an outage. With 'AT+COPS=1,2,"26201"', manual mode (1) is selected and the numeric identifier setting (2) is used to set operator (26201). The numeric id of the operator needs to be set based on the preferred network from 'AT+COPS=?'.

PLMN Connection Process

After setting a registration process with 'AT+COPS=...', the modem will try to connect to the Public Land Mobile Network. This can take some time to respond with 'OK'. Afterwards, the connection can be checked with 'AT+COPS?' and 'AT+CREG?' as usual.

PLMN Format Selection

The format of the current operator listing returned by 'AT+COPS?' can be set with 'AT+COPS=3,<format>'. Valid formats are (0) long, (1) short, (2) numeric.

Wrap Up

The SIM800L can be configured for manual, automatic or manual/automatic network registration. For more details see the SIM800L AT Command manual from the manufacturer.