The SIM808 with Leonardo mainboard is an Arduino card developed by DFRobot for multiple purposes, with an integrated quad-band GSM/GPRS and GPS module. It has a 4-layer PCB design and is the size of a UNO board. This latest version has better stability than previous ones. It can be used for applications such as GPRS network nodes, remote communications, GPS positioning and real-time monitoring, and IoT. Its specifications include an ATmega32u4 microcontroller, 20 digital I/O pins, 12 analog input pins, and 32KB flash memory. It operates at 5V and can be powered by USB, VIN, or a 3.7V li-battery. The SIM808 is controlled using AT commands and has a horizontal position accuracy of <2.5m CEP. The board has various connectors and pins for different functions and can be controlled using code

 

Package Includes:

• 1 x DFRobot SIM808 with Leonardo

 

Features:

1. AVR Arduino microcontroller: ATmega32u4 (Bootloader: Arduino Leonardo) + GSM module: SIM808 GSM/GPRS/GPS module combined
2. The SIM808 module and Leonardo mainboard are integrated into a single board, making it easier to prototype GSM/GPRS and GPS applications.
3. A high update rate of 5Hz
4. Battery Usage Availability 
5. onboard MIC+ external microphone Jack available 
6. control the SIM808 module to enter or exit sleep mode 
7. SIM808 includes an integrated charging circuit for Li-Ion batteries which makes it very convenient for any user applications that support battery charging.
8. The board has an onboard antenna for both GSM and GPS, as well as a connector for an external GPS antenna.
9. The board can be powered by a wide range of voltage inputs, from 5V to 12V DC.
10. The board has several interfaces, including UART, I2C, and SPI, for communication with other devices.
11. The board also has a micro-USB port for programming and debugging.
12. The board comes with a set of sample codes and libraries to help developers get started with GSM/GPRS and GPS applications.

 

Description:

The SIM808 with Leonardo mainboard is an Arduino card developed by DFRobot for multi-purpose use. It features an integrated quad-band GSM/GPRS and GPS satellite navigation technology module, which allows for GPRS network nodes, remote communications, GPS positioning and monitoring in real-time, and Internet of Things (IoT) applications. The SIM808 module used in this card is the latest version, which offers improved stability compared to previous versions available on the market. The board utilizes an AVR Arduino microcontroller (ATmega32u4), which is supported by a bootloader based on the Arduino Leonardo. It has a 4-layer PCB design that allows the powerful card to fit into an UNO size, making it a more compact and cost-effective solution for developers. The SIM808 with Leonardo mainboard supports various input voltages, including 5V (USB), 7-23V (Vin), and 3.5-4.3V (BAT). It has 20 digital I/O pins, 12 analog input pins, and a clock speed of 16 MHz. The card also comes equipped with a SIM808 GSM/GPRS/GPS module that operates on a quad-band 850/900/1800/1900MHz 2G GSM network. The GSM module is compliant with GSM phase 2/2+ and offers GPRS multi-slot class 12/10 and GPRS mobile station class B capabilities. It is a Class 4 (2 W @ 850/900MHz) and Class 1 (1 W @ 1800/1900MHz) module. The SIM808 with Leonardo mainboard also includes Bluetooth compliance with 3.0 + EDR (not open in this version), and a Time-To-First-Fix that includes cold starts at the 30s (typical), hot starts at 1s (typical), and warm starts at 28s (typical). The GPS accuracy for the horizontal position is less than 2.5m CEP and offers an update rate of 5 Hz. The module is controlled via AT command (GSM07.07, 07.05, and SIMCom enhanced AT commands).

 

Principle of Work:

The SIM808 module on the board is a GSM/GPRS module with GPS functionality. It can connect to a cellular network using a SIM card and can transmit and receive data over the network using standard AT commands. The module also has a built-in GPS receiver, which can be used to obtain the device's location. The Leonardo mainboard on the SKU DFR0355 provides a microcontroller platform to control and interact with the SIM808 module. The board can be programmed using the Arduino IDE and various libraries, allowing developers to create custom applications and control the SIM808 module's functions. The ATmega32u4 microcontroller on the Leonardo mainboard communicates with the SIM808 module using the UART interface. The ATmega32u4 sends commands to the SIM808 module using the UART interface and receives responses from the module in the same way. The SIM808 module also sends GPS data to the ATmega32u4 using the UART interface. To use the board, you would typically connect it to a computer or other device via the micro-USB port. You would then use the Arduino IDE to write and upload code to the board, which would control the SIM808 module's behavior. For example, you could write code to send SMS messages, make phone calls, or obtain GPS coordinates. The board has several interfaces, including UART, I2C, and SPI, which allow it to communicate with other devices and sensors. This makes it possible to create complex applications that integrate the SIM808 module with other hardware and software components.

 

Pinout of the Module:

 

Num	Pin or Function	Description
1	RESET	Reset Leonardo MCU
2	USB	Connect with PC via Arduino USB port
3	Net	SIM808 network indicator Quick flashing: Finding Network Slow flashing(every 3 seconds): Registered to the network OFF: SIM808 chip is not powered on(Button: BOOT)
4	GSM	GSM/GPRS Antenna Connector
5	GPS	GPS Antenna Connector
6	RX/TX	Serial Port indicator: Rx: Will flash if data received Tx: Will flash if data sent
7	7-23V	External power supply jack, 7-23V DC
8	BAT	3.7V Li-battery power supply connector Available here
*9	BOOT	SIM808 Switch: Turn SIM808 module ON/OFF
10	Red jack	Arduino standard power pins
11	Blue jack	Arduino standard analog pins
*12	NO BAT?	Switch for Li-battery power supply
13	Headphone jack	Suggested Shopping
14	JP2	RI/DTR control pin of SIM808 module, see below for more info
15	ICSP	Arduino ICSP interface
16	MIC	Onboard Microphone
*17	MIC jack	External microphone jack
18	green jack	Arduino standard digital pins

 

 

Applications:

1. Vehicle Tracking and Fleet Management: The SIM808 module can be used to track the location of vehicles in real-time, and to monitor other parameters such as speed, fuel consumption, and engine status. This is useful for fleet management and logistics applications.
2. Remote Monitoring: The SIM808 module can be used to monitor remote assets such as weather stations, power stations, and pipelines. It can transmit data over the cellular network, allowing operators to monitor assets in real-time and respond to any issues or alarms.
3. Personal Tracking: The SIM808 module can be used in personal tracking devices, allowing users to track the location of family members or employees. This is useful for security and safety applications.
4. Security Systems: The SIM808 module can be integrated into security systems such as alarms and access control systems, allowing the system to send alerts and notifications over the cellular network.
5. Industrial Automation: The SIM808 module can be used in industrial automation applications, such as controlling and monitoring equipment and processes. It can transmit data over the cellular network, allowing operators to monitor and control equipment remotely.
6. Smart Agriculture: The SIM808 module can be used in agriculture applications, such as monitoring soil moisture, temperature, and other environmental parameters. This can help farmers optimize crop yields and reduce water usage.

 

Circuit:

 No need for a circuit we will toggle the onboard LED when a phone call is received:

 

Library:

To work with the SIM808_with_Leonardo_mainboard_SKU_DFR0355, you will need to use the AT command which you will find in the resources or an appropriate library. Here are three libraries that are specifically designed for this board:

1. DFRobot_SIM808: This is the official library provided by DFRobot, the manufacturer of the board. It includes examples of using the cellular and GPS features of the board, as well as functions for sending and receiving SMS messages, making and receiving calls, and connecting to the internet using GPRS.

To install the DFRobot_SIM808 library, follow these steps:

• Download the library from the DFRobot website or from the Arduino library manager.
• Unzip the downloaded file.
• Move the unzipped folder to the libraries directory of your Arduino IDE.
• Restart the Arduino IDE.

2. Adafruit FONA Library: This library was originally designed for Adafruit's FONA boards, but it also supports the SIM808 module used on the SIM808_with_Leonardo_mainboard_SKU_DFR0355. It includes functions for sending and receiving SMS messages, making and receiving calls, and connecting to the internet using GPRS.

To install the Adafruit FONA library, follow these steps:

• Open the Arduino IDE.
• Go to Sketch > Include Library > Manage Libraries.
• Search for "Adafruit FONA" and click "Install".
• Wait for the installation to complete.

3. TinyGPS++ Library: This library is specifically designed for parsing GPS data from NMEA sentences. It can be used in conjunction with the SIM808_with_Leonardo_mainboard_SKU_DFR0355 to retrieve GPS location data.

To install the TinyGPS++ library, follow these steps:

• Download the library from the TinyGPS++ GitHub repository.
• Unzip the downloaded file.
• Move the unzipped folder to the libraries directory of your Arduino IDE.
• Restart the Arduino IDE.

 

Code:

Example code that toggles the onboard LED on the SIM808_with_Leonardo_mainboard_SKU_DFR0355 when a phone call is received:

#include "SoftwareSerial.h"

// set up software serial for communication with SIM808 module
SoftwareSerial sim808Serial(8, 7);

void setup() {
  pinMode(LED_BUILTIN, OUTPUT);
  
  // start serial communication with the computer
  Serial.begin(9600);

  // start software serial communication with the SIM808 module
  sim808Serial.begin(9600);

  // turn on LED to indicate setup is complete
  digitalWrite(LED_BUILTIN, HIGH);
  delay(500);
  digitalWrite(LED_BUILTIN, LOW);
  delay(500);
  digitalWrite(LED_BUILTIN, HIGH);
}

void loop() {
  // check if a phone call has been received
  if (sim808Serial.available() > 0) {
    if (sim808Serial.find("+CLIP")) {
      // phone call received, toggle LED
      digitalWrite(LED_BUILTIN, !digitalRead(LED_BUILTIN));
      delay(500);
      digitalWrite(LED_BUILTIN, !digitalRead(LED_BUILTIN));
    }
  }
}

This code uses the SoftwareSerial library to communicate with the SIM808 module and sets up the onboard LED as an output. In the loop() function, the code checks if a phone call has been received by looking for the "+CLIP" indicator in the SIM808's response. If a phone call is detected, the onboard LED is toggled using digitalWrite() and a 500-millisecond delay.

 

Technical Details:

• AVR Arduino microcontroller: ATmega32u4 (Bootloader: Arduino Leonardo)
• Operating voltage: 5V
• Input Voltage: 5V(USB) / 723V(Vin) / 3.54.3V(BAT)
• Digital I/O pins: 20 (7 PWM: 3,5,6,9,10,11,13)
• Analog Input pins: 12
• Flash: 32 KB (bootloader: 4KB)
• SRAM: 2.5 KB
• EEPROM: 1 KB
• Clock Speed：16 MHz

• GSM module: SIM808 GSM/GPRS/GPS module
• Quad-band 850/900/1800/1900MHz – 2G GSM network
• GPRS multi-slot class 12/10
• GPRS mobile station class B
• Compliant to GSM phase 2/2+
  • Class 4 (2 W @ 850/900MHz)
  • Class 1 (1 W @ 1800/1900MHz)
• Bluetooth: Compliant with 3.0 + EDR (Not open in this version)
• Time-To-First-Fix
  • Cold starts: 30s (typ.)
  • Hot starts: 1s (typ.)
  • Warm starts: 28s (typ.)
• Accuracy: Horizontal position <2.5m CEP
• Update rate: 5Hz
• Control: AT command (GSM07.07, 07.05, and SIMCom enhanced AT commands)

• Dimension: 73*54mm

 

Resources:

• Related Document Download all.
  • DFR0355 SIM808 with Leonardo mainboard schematic V1.0
  • DFRobot355 Wiki
  • NEW SIM800 Series GNSS Application Note V1.00
  • SIM800 Series AT Command Manual V1.07
  • SIM808 Hardware Design_V1.00
  • SVG file

• Suggest Link
  • Ubidots, A cloud service to capture and make sense of sensor data ...

 

Comparison:

The SIM808_with_Leonardo_mainboard_SKU_DFR0355 and the SIM808_GPS_GPRS_GSM_Shield_SKU__TEL0097-DFRobot are based on the SIM808 module and offer similar functionality for cellular and GPS communication. However, there are some key differences between the two:

1. Form Factor: The SIM808_with_Leonardo_mainboard_SKU_DFR0355 is a compact, integrated board that includes the SIM808 module and an ATmega32U4 microcontroller, whereas the SIM808_GPS_GPRS_GSM_Shield_SKU__TEL0097-DFRobot is a shield that is designed to be stacked on top of an Arduino board.
2. Power Supply: The SIM808_with_Leonardo_mainboard_SKU_DFR0355 requires a 5V power supply, whereas the SIM808_GPS_GPRS_GSM_Shield_SKU__TEL0097-DFRobot can be powered from either a 5V or 3.3V source, making it more versatile in terms of power requirements.
3. Communication Interface: The SIM808_with_Leonardo_mainboard_SKU_DFR0355 communicates with a host device (such as a computer or microcontroller) using a serial interface, whereas the SIM808_GPS_GPRS_GSM_Shield_SKU__TEL0097-DFRobot communicates with an Arduino board using the SPI interface.
4. Additional Features: The SIM808_with_Leonardo_mainboard_SKU_DFR0355 includes a microcontroller, allowing it to be programmed independently and potentially reducing the need for an additional microcontroller board. On the other hand, the SIM808_GPS_GPRS_GSM_Shield_SKU__TEL0097-DFRobot includes a microSD card slot for data storage, which may be useful in certain applications.

The choice between the SIM808_with_Leonardo_mainboard_SKU_DFR0355 and the SIM808_GPS_GPRS_GSM_Shield_SKU__TEL0097-DFRobot depends on the specific requirements of the project and the available hardware resources.