Quectel BG770A-SN

The Quectel BG770A-SN series supports IoT-NTN (satellite), LTE Cat M1/Cat NB2, and EGPRS, offering ultra-low power consumption. It complies with 3GPP Release 17 standards, ensuring optimal performance for advanced IoT applications.

Prerequisites

• Monogoto iSIM profile

• BG770A-SN

Quick Navigation

• Set up EVB Kit

• Useful Links

Set up EVB Kit

Quectel BG770A-SN modem

Set up the EVB Kit

• Connect the LTE antenna and GPS antenna

Connect your PC to the EVB Kit

Use the USB to UART converter cable to connect your computer to the COM1 MAIN port of the EVB Kit

When using Windows, install the driver using the disk or USB stick provided by Quectel.

Connect to the EVB kit (WCH USB-Serial Ch A) using a terminal program. You can use PuTTY for Windows, or screen, minicom, or miniterm for Mac or Linux.

Once the modem has started, it will report:

RDY
APP RDY

Enter AT, if the connection with the BG770A-SN modem has been established, the board will answer with OK.

Connect the BG770A-SN to Monogoto

Keep the AT Commands manual next to you for more details about the commands. Click here to download the latest version.

Reset the modem to its default configuration:

Restore factory settings:

AT&F1

Set the error reporting to verbose, resulting in more descriptive error messages (optional):

AT+CEREG=2

Query device information

Request the product type, hardware, and firmware version:

AT+QGMR

Example response: BG770ASNAAR02A01_01.202.01.202

Request the IMSI (International Mobile Subscriber Identity):

AT+CIMI

Request the ICCID (Integrated Circuit Card ID), which is the identification number of the iSIM

AT%CCID

Check the SIM initialization selection policy is currently using:

AT%GETCFG="SIM_INIT_SELECT_POLICY"

Expected response: SIM_INIT_SELECT_POLICY:5. The last digit indicates the Active SIM: 0 indicates External (SIM card) 5 indicates Internal (iSIM)

Network Configuration

It is possible to let the modem select the network automatically.

Set the APN to data.mono:

AT+CGDCONT=1,"IP","data.mono"

automatically select modem

The modem can be configured to automatically select the most appropriate band or region without manual intervention.

at+qcfg="band",0x0,0x0,0x0,0x7

Although the modem may support many different NTN bands,

Band 23 = Canada

band 255 = L band Global (Taiwan, Australia, New Zealand, Japan)

band 256 = S band Europe

Enable GNSS

AT+QCFG="ntn/pos","ignss",1   

Reboot module

AT+CFUN=1,1

Disable radio

AT+CFUN=0

Configure Radio Access Technology (RAT)

Configure the modem to only use NB-IoT NTN not LTE Cat-M1:

AT+QCFG="iotopmode",3,1

Enable TA and SIB notifications

AT+QCFG="ntn/ev","ta",1
AT+QCFG="ntn/ev","sib",1

Send registration status

AT+CEREG=2

Enable radio

AT+CFUN=1

Wait for a response::

+QCFG="ntn/ev","SIB31"
+QCFG="ntn/ev","TA","RACH",495,4982,190181
+QCFG="ntn/ev","TA","TAC",1,148,190360
+CEREG: 5,"07ED","002C480D",9

Check the current network registration status

AT+CEREG?

Query the signal measurement

request a specific network measurement, such as signal strength, noise levels, or other metrics:

AT%MEAS="8"

Example response: %MEAS:Signal Quality:RSRP= -115,RSRQ= -15,SINR= -3,RSSI= -120.

Reports the information of serving cells

AT+QENG="servingcell"

Example response:

+QENG: "servingcell","NOCONN","eMTC","FDD",901,98,2C480D,29,7699,255,1,1,7ED,-122,-8,-114,5,0

Check the radio signal strength and signal quality:

AT+CSQ

+CSQ returns 2 values separated by a comma. The first value represents the signal strength and provides a value between 0 and 31; higher numbers indicate better signal strength. The second value represents the signal quality indicated by a value between 0 and 7. If AT+CSQ returns 99,99, the signal is undetectable or unknown.

Validate if your device received an IP address:

AT+CGPADDR

Expected response: +CGPADDR: 1,XX.XXX.XX.XXX

Do you see an IP address? Congratulations! You’ve successfully connected the Quectel modem to Monogoto 🎉

Test the connection by sending a UDP payload

A UDP payload test when the modem has an active data connection with a Satellite.

Send UDP Payload to the IP address 34.192.142.126:

AT%SOCKETCMD="ALLOCATE",1,"UDP","OPEN","34.192.142.126",7,12345

response:

%SOCKETCMD:1
OK

Set and Active UDP Socket

AT%SOCKETCMD="SETOPT",1,36000,1
AT%SOCKETCMD="ACTIVATE",1

response:

OK

Send UDP Socket

AT%SOCKETDATA="SEND",1,13,"48656C6C6F2C20776F726C6421"

response:

%SOCKETDATA:1,13
OK
%SOCKETEV:1,1

info UDP Socket

AT%SOCKETCMD="INFO",1

response:

%SOCKETCMD:"ACTIVATED","UDP","10.22.243.30","34.192.142.126",12345,7
OK

Close UDP Socket

AT%SOCKETCMD="DELETE",1

response:

OK

Test the connection by sending a PING

A PING test can be performed to test if the modem has an active data connection with a mobile network.

When cellular modems are idle for a long period of time, cell towers might drop the data connection to save resources. Sending regular PINGs is a good method for testing the data connection, as well as for keeping the connection alive because the operator registers your device as being actively used.

Send 5 PINGs to IP address 8.8.8.8:

AT+QPING=1,"8.8.8.8",5

Example response:

+QPING: 0,"8.8.8.8",32,543,255
+QPING: 0,"8.8.8.8",32,396,255
+QPING: 0,"8.8.8.8",32,262,255
+QPING: 0,"8.8.8.8",32,299,255
+QPING: 0,4,4,0,262,543,375

Transition Between Satellite Network and Public Network

When transitioning between satellite and public networks using the Murata Kit use the following commands:

Command for Switching to Public Network:

AT+QCFG="iotopmode",0

This command activates the CAT-M mode for public networks, allowing the device to switch from satellite connectivity to a cellular public network.

Command for Switching Back to Satellite Network

AT+QCFG="iotopmode",3

This command activates the NBNTN mode, returning the device to satellite network connectivity.

Useful Links

• Quectel BG770A-SN product page

• BG77xA-GL_TE-B_User_Guide_V1.1