User Manual

SARA-R4 series-AT commands manual
UBX-17003787 - R16
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7Network service
Page 50 of 401
parameters are returned only if <n>=3 and the MT is not registered, but it is currently searching a new operator
to register to (<stat>=2) or if the registration is denied (<stat>=3).
When <n>=2, in UMTS RAT, unsolicited location information can be received if the network sends the
UTRAN INFORMATION MOBILITY message during dedicated connections; in the latter cases the reported
<ci> might be not correct because the UE in DCH state cannot read broadcast system information before
the change of serving cell. In contrast, in GSM RAT no unsolicited location information is received during
a CS connection.
The DTE application should set a reasonable timer (10 s) when receiving the +CREG: 3 URC, since this
might be due to the fact that the LTE registration was rejected (SIM not enabled for LTE RAT, wrong APN
during the initial default bearer setup in the EPS attach procedure and other temporary reject causes).
If the MT also supports GPRS services and/or EPS services in E-UTRAN, the +CGREG / +CEREG set and
read command result codes, where supported, apply to the registration status and location information
for those services.
7.7.2Syntax
Type Syntax Response Example
Set AT+CREG=[<n>] OK AT+CREG=1
OK
Read AT+CREG? +CREG: <n>,<stat>[,<lac>,<ci>[,
<AcTStatus>]]
OK
+CREG: 0,0
OK
Test AT+CREG=? +CREG: (list of the supported <n>s)
OK
+CREG: (0-2)
OK
URC +CREG: <stat>[,[<lac>],[<ci>][,
[<AcTStatus>][,<cause_type>,
<reject_cause>]]]
+CREG: 1,"4E54","44A5"
7.7.3Defined values
Parameter Type Description
<n> Number Network registration URC configuration. Allowed values:
• 0 (default value and factory-programmed value): network registration URC disabled
• 1: network registration URC enabled
• 2: network registration and location information URC enabled
• 3: network registration and reject cause URC enabled
<stat> Number Network registration status. Allowed values:
• 0: not registered, the MT is not currently searching a new operator to register to
• 1: registered, home network
• 2: not registered, but the MT is currently searching a new operator to register to
• 3: registration denied
• 4: unknown (e.g. out of GERAN/UTRAN/E-UTRAN coverage)
• 5: registered, roaming
• 6: registered for "SMS only", home network (applicable only when <AcTStatus>
indicates E-UTRAN)
• 7: registered for "SMS only", roaming (applicable only when <AcTStatus> indicates
E-UTRAN)
• 8: attached for emergency bearer services only (see 3GPP TS 24.008 [12] and 3GPP
TS 24.301 [68] that specify the condition when the MS is considered as attached
for emergency bearer services)
• 9: registered for "CSFB not preferred", home network (applicable only when
<AcTStatus> indicates E-UTRAN)
• 10: registered for "CSFB not preferred", roaming (applicable only when <AcTStatus>
indicates E-UTRAN)
<lac> String Two bytes location area code or tracking area code (if <AcTStatus>=7) in
hexadecimal format (e.g. "00C3"). The value FFFF means that the current <lac> value
is invalid.
<ci> String From 2 to 4 bytes cell ID in hexadecimal format (e.g. "A13F" or "129080B"). The value
FFFFFFFF means that the current <ci> value is invalid.