Skip to main content
All CollectionsTroubleshooting guides and FAQsUseful AT commands
AT+CGREG: Modes, parameters, and examples
AT+CGREG: Modes, parameters, and examples

This article is a practical overview of how to use the AT+CGREG command.

P
Written by Peter Skov Bornerup
Updated over a month ago

AT+CGREG is an AT command for the GPRS registration status of the device.

Overview

Command

Example response(s)

Info

AT+CGREG=?

+CGREG: <n>
OK
​
+CGREG: (0-2)
OK

Checks supported configurations.
​

<n> = list of supported configurations.

AT+CGREG?

+CGREG: <n>,<stat>
OK
​
+CGREG: <n>,5
OK
​
​

+CGREG: <n>,1
OK

Get the current registration status.


​<n> = current configuration value.
​

<stat> = network registration status.

<stat> is 1 = registered to the home network, and 5 = registered to a roaming network.

AT+CGREG=0

OK

Disables Unsolicited Result Codes.

AT+CGREG=1

OK

Enables Unsolicited Result Codes (receive automatic updates on registration status).

AT+CGREG=2

OK

Enables network registration and location information Unsolicited Result Codes.

AT+CGREG=?

AT+CGREG=? is a test command that returns the list of supported network configurations.
​

AT+CGREG?

AT+CGREG? is a read command for the GPRS registration status of the device. Receiving “registered” status from AT+CGREG? indicates that the device can access the internet.
​

Expected responses include +CGREG: <n>,5 and +CGREG: <n>,1.
​

  • The n indicates the Unsolicited Result Code (URC) status,

  • “5” indicates that the modem is registered to a network and is roaming, and

  • “1” means the device is registered to the home network.

AT+CGREG=0

AT+CGREG=0 is a set command that disables the return of Unsolicited Response Codes (URCs) when network registration occurs.
​

In other words, there is no automated update on network registration.
​

AT+CGREG=1

AT+CGREG=1 is a set command that enables Unsolicited Response Codes (URCs) for the packet-switched network status.
​

Basically, this command tells the modem to respond when the network status changes, without having to manually check connectivity using AT+CGREG?.
​

AT+CGREG=2

AT+CGREG=2 is a set command that enables network registration and location information Unsolicited Result Codes (URCs).
​

+CREG, +CGREG & +CEREG

What are the differences between +CREG, +CGREG, and +CEREG?
​

  • +CREG queries the registration to the circuit switched network, aka GSM networks.

  • +CGREG and +CEREG query registration to the packet switched networks, aka networks which allow access to the internet.

  • +CGREG queries the registration to GPRS network.

  • +CEREG queries the registration to LTE or newer network technologies.

If you’re using modems with both GPRS and LTE technologies, use both AT+CGREG? and AT+CEREG?. The modem will report <n>,4 to the technology that is currently not active.
​

Defined values

<n> = Network registration unsolicited result code mode.

  • 0 = Disable network registration unsolicited result code.

  • 1 = Enable network registration unsolicited result code +CGREG: <stat>.

  • 2 = Enable network registration and location information unsolicited result code +CGREG: <stat>[,<lac>,<ci>,<AcT>,<rac>].

<stat> = Current network registration status.

  • 0 = Not registered and the modem is not currently searching for an operator to register to.

  • 1 = Registered to the home network.

  • 2 = Not registered, but the modem is currently trying to attach or is searching for an operator to register to.

  • 3 = Registration denied.

  • 4 = Unknown.

  • 5 = Registered to a roaming network.

  • 6 = Registered for “SMS only”, home network (applicable only when <Act> indicates E-UTRAN)

  • 7 = Registered for “SMS only”, roaming (applicable only when <Act> indicates E-UTRAN)


​<lac> = Location area code.

String type; two byte location area code in hexadecimal format (e.g. “00C3” equals 195 in decimal).
​

<ci> = Cell ID
String type; four byte UTRAN/GERAN/E-UTRAN cell ID in hexadecimal format.
​

<AcT> = Access technology of the registered network.

  • 0 = GSM

  • 1 = GSM Compact

  • 2 = UTRAN

  • 3 = GSM w/EGPRS

  • 4 = UTRAN w/HSDPA

  • 5 = UTRAN w/HSUPA

  • 6 = UTRAN w/HSDPA and HSUPA

  • 7 = E-UTRAN

  • 8 = EC-GSM-IoT (A/Gb mode)

  • 9 = E-UTRAN (NB-S1 mode)

Interpreting this; 0 would typically be 2G connectivity, 7 is typically LTE (including LTE-M), and 9 is typically NB-IoT.
​
​​<rac> = Routing area code.

String type; one byte routing area code in hexadecimal format.

Notes

The information in this article is predominantly based on the SIMCOM 7020 series.

Did this answer your question?