SKU_TEL0163_A7670G_CAT1_4G_Communication_Module WIKI

1. Introduction

This is a 4G CAT1 module, supporting wireless communication modes such as LTE-TDD/LTE-FDD/GSM, with global coverage. Its maximum downlink speed of 10Mbps and uplink speed of 5Mbps will provide you with a dependable low-speed data transmission experience.

Furthermore, this module integrates a plethora of network protocol support, including TCP/IP/IPV4/Multi-PDP/FTP/FTPS/HTTP/HTTPS/DNS, offering you a variety of options for your data transmission needs. Whether it's simple data transfer or intricate network communication, it can all be effortlessly accomplished. Additionally, SMS functionality has been thoughtfully included, supporting MT/MO/CB/Text and PDU modes, allowing for flexible text message interaction.

In terms of design, the module comes with power indicator lights, network signal indicator lights, antenna interfaces, and other features that greatly facilitate your project development and validation process. You can easily monitor the module's status and connectivity, enabling more efficient debugging and testing. Combined with detailed AT commands, the use of our provided communication routines will allow you to quickly grasp module operation and configuration, thus expediting the achievement of your project goals.

This series of 4G products differentiates the modules based on communication speed and satellite positioning. The table below presents the functional parameters of each 4G product for your reference during selection:

2. Technical Specifications:

• Operating Voltage: DC 5V
• Push-lock SIM card socket
• Module Interfaces:
  • One PH2.0 UART input interface
  • One USB-Type C input interface
  • One power input interface
  • One audio output interface
• External Power Sources:
  • Terminal connectors: 5-12V
  • USB-Type C: 5V
• Dual Antennas:
  • ANT: 4G signal antenna interface
• Network Frequency Support:
  • LTE-TDD:B38/B39/B40/B41
  • LTE-FDD: B1/B2/B3/B4/B5/B7/B8/B12/B13/B18/B19/B20/B25/B26/B28/B66
  • GSM: 850/900/1800/1900MHz
• 4G Communication Rate: CAT1 (Uplink speed: 5Mbps, Downlink speed: 10Mbps)
• LED Status Indicators
  • Power Status
  • Network Status
• Applicable Regions: Worldwide
• Operating Temperature Range: -40°C to 85°C
• Product Dimensions: 60×52mm

3. Functional Diagram

Important Notes:

1.When using the PH2.0 socket for module communication, an external power supply of 5V-12V is required.

2.Net - Network signal indicator:

• Steady blue light: Searching for a network.
• Rapid blue flashes (once every 1 second): Network registration completed.

4. Dimensional Diagram

5. Common AT Commands

Note: This AT command is case-insensitive.

6. Sample Applications

Hardware Preparation:

• A7670G 4G Module x1
• Windows 11 PC x1
• SIM Card x1
• USB Data Cable x1

Software Preparation:

Driver Installation:

• SIMCOM Driver [Download Link]

Install the driver, unzip the package, and locate the extracted files.

Select "Next"

Please install the driver file onto the disk of your choice.

Restart the system, and the driver installation will be successful.

Using Windows 10 as an example, after successfully installing the driver following the aforementioned method, connect the USB-type C interface on the module and wait for the appearance of the "Simcom Port" in the computer device management interface.

The "Simcom Network Adapter Driver" will appear in the network adapter interface.

(1)Initiating and Receiving Phone Calls

Demonstration of Making and Receiving Phone Calls:

1.Send the ATD138xxxxxxxx; command to dial the target user's phone number. Note: Remember to add a semicolon at the end of the command.

VOICE CALL: BEGIN: Indicates the call has started. After hanging up, you will see VOICE CALL END: xxxxx and NO CARRIER, indicating the end of the call.

RING: Indicates an incoming call. Use the ATA command to answer the call.

VOICE CALL BEGIN: Indicates that the call has been answered.

2.During the call, use the AT+CHUP command to hang up.

(2)Transmitting Text Messages

Demonstration of Sending Messages and Querying:

1.Send the AT+CMGF=1 command to set the SMS mode to TEXT mode.

2.Then, input AT+CMGS="138xxxxxxxx" to send a message to the target phone. You will receive the ">" prompt, then input the message you want to send. Note: When dispatching the contents of the message, omit the carriage returns and line breaks.

3.After composing and sending the message, confirm it and check "SendHEX" to send the message in 16-bit hexadecimal. Send 1A (used to instruct the module to perform the sending operation), and receive +CMGS: ok, indicating successful transmission.

These are the steps for sending SMS messages. If you want to inquire about the number of existing messages and the message limit, you can use the AT+CPMS? command. Note: The number of existing messages starts from 1.

You can also input AT+CMGR=X to read the specific content of the Xth message or use AT+CMGD=X to delete the Xth message.

(3)MQTT Connection

Demonstration of Sending Messages to the Target Server:

This example demonstrates sending a predefined message to the Easy IoT platform using AT commands with the A7670G module.

Enter Easy IoT. If you do not possess an account, you may commence by registering one.

Upon successful login, proceed to open your workspace. Retrieve your credentials: username, password. Then, proceed to add a novel device, denoted as a Topic, and meticulously document the aforementioned three pivotal parameters.

1.Open the SSCOM assistant and send the AT+CMQTTSTART command to initiate the module's MQTT service.

2.Send the AT+CMQTTACCQ=0,"EASYIOT" command (set the connection mode to TCP and customize the username as "EASIOT").

3.Send the AT+CMQTTCONNECT=0,"tcp://iot.dfrobot.com:1883",120,1,"user","password" command (TCP, set the server address to Easy IoT, set the message interval to 120 seconds [maximum 64800], enter the account [user] and password [password] obtained from the Easy IoT platform, and clear user information when the device is offline).

4.Send the AT+CMQTTSUB=0,9,1 command (parameter 1 is the client parameter, parameter 2 sets the number of message publications, parameter 3 sets the publication timeout interval in seconds) and wait for the ">" prompt. Then send the topic obtained from the Easy IoT platform.

5.Send the AT+CMQTTTOPIC=0,9 command (set the publishing topic, with parameter 1 as the client parameter and parameter 2 as the topic data length). Wait for the ">" prompt and then send the topic obtained from the Easy IoT platform.

6.Send the AT+CMQTTPAYLOAD=0,12 command (set the message content, similar to AT+CMQTTTOPIC, and directly send characters afterward; ensure the length matches). Wait for the ">" prompt and then send the message content (HELLODFROBOT).

7.Send the AT+CMQTTPUB=0,1,60 command (publish the message, parameter 1 is the client parameter, parameter 2 sets the number of message publications, and parameter 3 sets the publication timeout interval in seconds).

8.Finally, access the Easy IoT workspace, check the detailed information of the created topic, and verify that the message (HELLODFROBOT) sent from the module has been received.

Note: Line breaks should also be entered when inputting topics and messages.

(4)Audio Playback

Recording and Playing Back WAV Audio - Demonstration

1.Input AT+CREC=1,"c:/rec.wav" to start recording WAV audio and save it to the local path e:/rec.wav. A return of +CREC: 1, OK indicates successful recording, while ERROR indicates recording failure. *Note: *Use only English characters when sending AT commands.

2.Send AT+CREC=0 to stop recording WAV audio. To play the previously recorded WAV audio, use the command AT+CCMXPLAYWAV="c:/rec.wav",0,255. If you want to stop playback, you can use the AT+CCMXSTOPWAV command.

Please take note: The audio file should be placed within the "C:/" directory.

(5)Power Saving Mode

(6)Sleep Mode

In sleep mode, the module can still receive paging, SMS, and voice calls from the network.

7. Arduino Example Code

In addition to the methods mentioned earlier for controlling the A7670G module via PC and onboard USB virtual serial port, you can also use Arduino to send AT commands to debug and operate the A7670G module.

In this example, we will modify the baud rate of the A7670G module and the main controller.

Hardware Preparation:

• A7670G 4G Module x1
• Windows 11 PC x1
• SIM card x1
• DFRduino UNO R3 x1
• 5V-12V external power supply

Software Preparation:

• Latest version of Arduino IDE Download Arduino IDE

Connection Diagram and Steps:

Steps

1. Insert the SIM card into the expansion board and connect it to the DFRduino UNO R3 mainboard as shown in the diagram. Connect an external power supply as well.
2. Wait for the SIM card to register on the network. The NET status indicator LED should start flashing rapidly (once every 1 second).
3. Download the program below to the DFRduino UNO R3 and open the serial monitor, setting the baud rate to 115200.

#include "SoftwareSerial.h"
   SoftwareSerial softSerial(/*rx =*/4, /*tx =*/5);

void setup() {

  Serial.begin(115200); // Initialize the hardware UART
  softSerial.begin(115200); // Initialize the software UART
  Serial.println("For example, if you type AT\\r\\n, OK\\r\\n will be responsed!");
  Serial.println("Enter your AT command :");
}

void loop() {
  if (softSerial.available()) {
    char data = softSerial.read(); // Read data from the software UART
    Serial.write(data); // Transmit to the hardware UART
  }

  if (Serial.available()) {
    char data = Serial.read(); // Read data from the hardware UART
    softSerial.write(data); // Transmit to the software UART
  }
}

Transmitting AT commands, receiving "OK" as the serial response, signifies successful communication.

Please note that when using an Arduino UNO for serial communication, the module's default communication rate is 115200. The oscillation frequency of the external crystal can result in significant baud rate errors, causing data corruption. It is necessary to set both the module's baud rate and the program's baud rate to 9600.

To achieve this, send the command "AT+IPREX=9600" to set the module's baud rate to 9600 after a restart.

Subsequently, modify the UNO's serial communication rate and re-upload the program.

#include "SoftwareSerial.h"
   SoftwareSerial softSerial(/*rx =*/4, /*tx =*/5);

void setup() {

  Serial.begin(9600); // Initialize the hardware UART
  softSerial.begin(9600); // Initialize the software UART
  Serial.println("For example, if you type AT\\r\\n, OK\\r\\n will be responsed!");
  Serial.println("Enter your AT command :");
}

void loop() {
  if (softSerial.available()) {
    char data = softSerial.read(); // Read data from the software UART
    Serial.write(data); // Transmit to the hardware UART
  }

  if (Serial.available()) {
    char data = Serial.read(); // Read data from the hardware UART
    softSerial.write(data); // Transmit to the software UART
  }
}

Using a baud rate of 9600, send "AT" and "AT+IPREX?" to the serial port, which should return "OK" and the current baud rate value of 9600, confirming the successful modification of the communication rate.

8. Internet Access on LattePanda

Hardware Preparation:

• A7670G 4G Module ×1

• LattePanda ×1

• 11.6-inch FHD Touch Screen ×1

• Keyboard ×1

Operation steps:

• Insert the SIM card into the A7670G 4G Module slot, then connect the module and LattePanda via USB, and also connect the keyboard and touch screen to LattePanda.

• Power on and wait for LattePanda to boot

• Under network status, install the SIMCOM driver according to the method in the sample application

  • SIMCOM driver [Download address]

• After installation, restart LattePanda and check the Simcom port in the device management interface to confirm that the driver of the 4G module has been successfully installed.

• Finally, find the 4G module as a new network connection in "Change Adapter Settings", right-click and select "Connect", and you can use the 4G module as a network card for LattePanda.

9. Querying Result Codes and Their Meanings

More Document Downloads

• TEL0163_A7600G 4G Module_Schematic.pdf
• A76XX_Series_AT_Command_Manual_V1.09.pdf
• TEL0163_2D_CAD.pdf
• TEL0163_2D_CAD.rar
• TEL0163_3D_STP.rar

FAQ

For any questions, advice or cool ideas to share, please visit the DFRobot Forum.