4G IHC-3308GW has single wifi version and wifi+4g version, please confirm that the machine used is equipped with 4G module. Resolution method: Check the number of antennas, if there is only one antenna interface, it is the single wifi version. If there are two antenna interfaces, it is the wifi+4g version. The 4G module used is "EC200S-CN", for "Buildroot" or "Ubuntu" system, after power on, the system will automatically dial SIM card connection 4G antenna connection Manual AT command dial-up networking If the system cannot dial normally, you can use AT commands to troubleshoot the problem manually. Confirm whether the EC200S-CN module starts normally, and the usb0 network card corresponds to the EC200S-CN module #ifconfig usb0 usb0 Link encap:Ethernet HWaddr AE:0C:29:A3:9B:6D inet addr:192.168.43.100 Bcast:192.168.43.255 Mask:255.255.255.0 inet6 addr: fe80::ed5d:84b6:c27c:3825/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:18 errors:0 dropped:0 overruns:0 frame:0 TX packets:39 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes: 3456 (3.3 KiB) TX bytes: 3811 (3.7 KiB) Configure serial port properties If it is an Ubuntu system, it needs to be configured # stty -F /dev/ttyUSB2 icrnl opost onlcr icanon echo echoe Query module status # cat /dev/ttyUSB2 & # echo AT+QCFG="usbnet" > /dev/ttyUSB2 If it returns +QCFG: "usbnet",1, that is ECM status Module is configured to ECM NIC status echo AT+QCFG="usbnet",1 > /dev/ttyUSB2 Dial echo AT+QNETDEVCTL=1,1,1 > /dev/ttyUSB2 ping external network Other AT commands disconnect dial echo AT+QNETDEVCTL=0,1,1 > /dev/ttyUSB2 Check the strength of the antenna signal, return the value "0-31,99", try to ensure that the signal strength is "26-31,99" echo "AT+CSQ" > /dev/ttyUSB2 Check whether the sim card or IoT card is inserted, and return to READY normally echo "AT+CPIN?" > /dev/ttyUSB2 Check the operator, such as China Unicom CHN-UNICOM, mobile "CHINA MOBILE" echo "AT+COPS?" > /dev/ttyUSB2 Check whether the traffic service of the sim card is normal echo "AT+CGATT?" > /dev/ttyUSB2 Return +CGATT: 1 means attached, +CGATT: 0 means detached, when returning +CGATT: 0, please check whether the traffic service of the card is normal Uart The expansion board expands multiple serial ports for use, including 3 "RS485" and 1 "RS232". The kernel already supports the above serial port functions by default. The device files corresponding to each serial port are as follows: RS485_1: /dev/ttysWK0 RS485_2: /dev/ttysWK1 RS485_3: /dev/ttysWK2 RS232 : /dev/ttysWK3 Take RS485_1 as an example: connect Connect the A and B pins of RS485_1 to the A and B pins of the host serial adapter (USB to 485 to serial port module) respectively. Open the serial terminal of the host Open kermit in the terminal and set the baud rate: $ sudo kermit C-Kermit> set line /dev/ttysWK0 C-Kermit> set speed 9600 C-Kermit> set flow-control none C-Kermit > connect "/dev/ttyUSB0" is the device file of the USB-to-serial adapter recognized by the host. send data Run the following command on the device: echo "Firefly RS485 test..." > /dev/ttysWK0 The serial terminal in the host can receive the string "Firefly RS485 test...". Receive data First run the following command on the device: cat /dev/ttysWK0 Then enter the string "Firefly RS485 test..." in the serial terminal of the host, and the same string can be seen on the device side. CAN connect Just connect the "CANH", "CANL" of the device and the "CANH", "CAHL" of the communication terminal correspondingly. send data ip link set can0 down ip link set can0 type can bitrate 250000 ip link set can0 up cansend can0 123#1122334455667788 Receive data ip link set can0 down ip link set can0 type can bitrate 250000 ip link set can0 up candump can0 loopback mode test ip link set can0 down ip link set can0 type can bitrate 50000 loopback on ip link set can0 up candump can0 & cansend can0 123#11223344556677 DIN The gateway supports one optocoupler isolation interface, where "DI" corresponds to "INPUT1" in the hardware schematic diagram, and "COM" corresponds to "INPUT_COM" in the hardware schematic diagram. Circuit Schematic Detection When "INPUT1", "INPUT_COM" are on, "GPIO_INPUT1" will detect a low level; when "INPUT1", "INPUT_COM" are off, "GPIO_INPUT1" will detect a high level. The corresponding "GPIO" ports are as follows: GPIO_INPUT1: GPIO1_A6, 38 The detection method is as follows: # apply for GPIO echo 38 > /sys/class/gpio/export # set as input echo in > /sys/class/gpio/gpio38/direction # read level value cat /sys/class/gpio/gpio38/value DOUT The gateway supports one relay interface, "DO" corresponds to "OUTPUT1" in the hardware schematic diagram, and "COM" corresponds to "RELAY_COM1" in the hardware schematic diagram. Circuit schematic control When "RELAY_CTL1" outputs a low level, "OUTPUT1", "RELAY_COM1" are disconnected; when "RELAY_CTL1" outputs a high level, "OUTPUT1", "RELAY_COM1" are turned on. The corresponding "GPIO" ports are as follows: RELAY_CTL1: GPIO1_B2, 42 The control method is as follows: # apply for GPIO echo 42 > /sys/class/gpio/export # set as output echo out > /sys/class/gpio/gpio42/direction # Set the level value, 1 / 0 echo 1 > /sys/class/gpio/gpio42/value LED The gateway supports 6 customizable LED lights, and the corresponding GPIO ports are as follows: The control method is as follows, taking L1 as an example: # Bright echo 1 > /sys/class/leds/firefly\:green\:L1/brightness # off echo 0 > /sys/class/leds/firefly\:green\:L1/brightness