Quectel BG95 BG96 BG77 extended configuration settings
The article provides some best practices for the most commonly used QCFG commands.
Advised settings
The following settings are advised for non-NB-IoT markets:
Ensures LTE and GSM scanning
Ensures LTE scanning first
Ensures no NB-IoT scanning
The following settings are generally advised:
Ignores SIM preference
PS + CS to support legacy SMS
Read the sections below to understand the above-advised settings.
Introduction
Quectel offers extended configuration settings for the BG series of modules using the AT+QCFG commands. These settings may impact the proper working of the KORE OmniSIM.
Examples include:
In some cases, the attach time of the KORE OmniSIM Reach may be impacted by the fact that the module scans all the NB-IoT bands.
A network combined attach is necessary for proper legacy SMS support.
Background
Scanning NB-IoT bands can consume a lot of time, especially when NB-IoT is unavailable locally. During that scan period, the module can be busy and not be responsive for renewing IMSIs as requested by the SIM. This does not affect the Multi IMSI selection process, as the SIM is not getting information from the module, it will wait with switching IMSI, but it will extend the time it takes to attach.
It could be the case that the module accepts new IMSIs from the SIM but cannot start an attach as the scan time is too long.
SMS is supported worldwide by C7 signaling, often called Circuit Switched. The device must request Packet Switched + Circuit Switched connection to force a combined network attach to support C7 signaling.
Checking the settings
Scan mode
Check using the following AT command:
The module will reply with one of the following modes:
Depending on the market or region, it may be advised to set the scan mode to GSM only or LTE only.
Example: All 2G and 3G networks will be shut down in the USA at the end of 2022. GSM scanning is of no use.
Note: New scan mode is not applicable for BG77 (LTE only).
Scan Sequence
Check using the following AT command:
The module will reply with one of the following modes:
Scanning NB-IoT
Check using the following AT command.
The module will reply with one of the following modes:
Preferred Access Technology
Check using the following AT command.
AT+QCFG="simeffect"
The module will reply with one of the following modes:
Legacy SMS support
Check using the following AT command.
The module will reply with one of the following modes:
Although it sounds not logical to use PS+CS, it should be noted that this setting determines the back-end of the networks, not the radio access. This setting doesn’t force the device to use 2G/3G technology.
Default settings
BG77 - Default settings
The following are the factory configuration setting of the BG77 module
+QCFG: "nwscanmode", ERROR
+QCFG: "nwscanseq",00
+QCFG: "iotopmode",2
+QCFG: "simeffect",1
+QCFG: "servicedomain",2
BG95 M3 - Default settings
The following are the factory configuration setting of the BG95 module
+QCFG: "nwscanmode", 0
+QCFG: "nwscanseq",00
+QCFG: "iotopmode",2
+QCFG: "simeffect",1
+QCFG: "servicedomain",2
BG96 - Default settings
The following are the factory configuration setting of the BG96 module
+QCFG: "nwscanmode", 0
+QCFG: "nwscanseq",00
+QCFG: "iotopmode",2
+QCFG: "simeffect",ERROR
+QCFG: "servicedomain",2
Last updated
Was this helpful?
