> 8.5 | AT+CREG Network registration

> The AT+CREG command serves to verify the network registration status of the ME. For this purpose two types of URCs are available.
> The AT+CREG read command returns the URC presentation mode <n> and an integer <stat> that shows the registration status of the ME. The location information elements <lac> and <ci> are returned only when <n>=2 and ME is registered to the network.
> Syntax

> Test Command AT+CREG=?
> Response(s)
> +CREG: (list of supported<n>s)
> OK

> Read Command AT+CREG?
> Response(s)
> +CREG: <n>, <stat>[, <lac>, <ci>]
> OK
> ERROR
> +CME ERROR: <err>

> Write Command AT+CREG=[<n>]
> Response(s)
> OK
> ERROR
> +CME ERROR: <err>

> Reference(s) |  | PIN |  | ASC0 | ASC1 | USB | MUX1 | MUX2 | MUX3 |  |  | Charge | Q | Last
> GSM 07.07 |  | - |  | + | + | + | + | + | + |  |  | - | - | -

> Unsolicited Result Codes
> URC 1
> If <n>=1 and there is a change in the ME network registration status:
> +CREG: <stat>
> URC 2
> If <n>=2 and there is a change in the ME network registration status or a change of the network cell:
> +CREG: <stat>[, <lac>, <ci>]
> Parameter Description

> <n>(num)(&W)(&V)

> [0](&F)
> Disable +CREG URC
> 1
> Enable URC +CREG:<stat> to report status of network registration
> 2
> Enable URC +CREG:<stat>[,<lac>,<ci>] to report status of network registration including location information. Optional parameters <lac> and <ci> will not be displayed during calls or if these values have not changed since last AT+CREG read command or since last indication by +CREG URC.

> <stat>(num)(&V)

> 0
> Not registered, ME is currently not searching for new operator
> Normally, status 0 occurs temporarily between two network search phases (status 2). However, if it persists, one the following reasons may apply:

> • | Automatic network selection is active, but probably there is

> - | no SIM card available

> - | no PIN entered

> - | no valid Home PLMN entry found on the SIM

> • | Manual network selection is active and the selected network is available, but login fails due to one of the following reasons:

> - | #11 ... PLMN not allowed

> - | #12 ... Location area not allowed

> - | #13 ... Roaming not allowed in this location area

> In either case, user intervention is required. Yet, emergency calls can be made if any network is available.
> 1
> Registered to home network
> 2
> Not registered, but ME is currently searching for a new operator
> The ME searches for an available network. Failure to log in until after more than a minute may be due to one of the following reasons:

> • | No network available or insufficient Rx level.

> • | The ME has no access rights to the networks available.

> • | Networks from the SIM list of allowed networks are around, but login fails due to one of the following reasons:

> - | #11 ... PLMN not allowed

> - | #12 ... Location area not allowed

> - | #13 ... Roaming not allowed in this location area

> After this, the search will be resumed (if automatic network search is enabled).

> • | The Home PLMN or an allowed PLMN is available, but login is rejected by the cell (reasons: Access Class or LAC).

> If at least one network is available, emergency calls can be made.
> 3
> Registration denied

> • | Authentication or registration fails after Location Update Reject due to one of the following reasons:

> - | #2 ... IMSI unknown at HLR

> - | #3 ... Illegal MS

> - | #6 ... Illegal ME

> Either the SIM or the MS or the ME are unable to log into any network. No further attempt is made to search or log into a network. User intervention is required. Emergency calls can be made, if any network is available.
> 4
> Unknown (not used)
> 5
> Registered, roaming
> The ME is registered at a foreign network (national or international network)

> <lac>(str)

> Two byte location area code in hexadecimal format (e.g. "00C3" equals 193 in decimal).

> <ci>(str)

> Two byte cell ID in hexadecimal format.
> Note

> • | After the "+CREG: 1" (or "+CREG: 5") URC and before the "^SSIM READY" URC it is not sure that outgoing and incoming calls can be made and short message functions executed. Emergency calls are possible. Outgoing and incoming calls are always possible AFTER having received the "+CREG: 1" (or "+CREG: 5") and "^SSIM READY" URCs. See also Section 23.1, Restricted access to SIM data after SIM PIN authentication.

> Example

> AT+CREG=2 | Activates extended URC mode.
> OK
> AT+COPS=0 | Forces ME to automatically search network operator.
> OK
> +CREG: 2 | URC reports that ME is currently searching.
> +CREG: 1,"0145","291A" | URC reports that operator has been found.