From Microduino Wiki
Revision as of 06:41, 12 August 2014 by Jasonsheng (talk)
Jump to: navigation, search
Language: English  • 中文

Microduino-GPRS/GSM module can get Microduino core board connected to the internet and achieve the function of sending and receiving messages when it is just inserted with a SIM card and follows some simple instructions.


  • ESD protection;
  • Capable of being charged by USB, li-ion or other power supply options;
  • Support automatic baud rate detection function;
  • Capable of sending AT instructions and data through the serial port;
  • Small, cheap, stackable and open;
  • Open hardware circuit design and Arduino compatible programming development environment;
  • Uniformed Microduino interface standard and rich peripheral modules, capable of having a fast and flexible connection and extension with other modules and sensors in accord with Microduino interface standard;
  • Easy to be integrated to pegboards with a 2.45-pitch female header connector interface.


Adopt SIM800L module to support four-band GSM/GPRS, whose working band is:GSM850, EGSM900, DCS1800 and PCS1900MHz.

  • Electrical characteristics
    • Working voltage:3.4V ~4.4V;
    • The current consumption is 0.7 mA under the Sleep Mode
  • GPRS data
    • The maximum data transmission rate of GPRS is 85.6 kbps;;
    • Build-in TCP/IP protocol;
    • Encoding format:CS-1, CS-2, CS-3 and CS-4;
    • Support Unstructured Supplementary Service Data (USSD)
  • Serial debugging
    • Support standard full-function serial as well as the transmission rate with a range from 1200bps to 115200bps;
    • Support the serial port multiplexing function complying with GSM 07.10 protocol;
  • Two Main Components:
    • SIM800L module
    • SIM card power and base plant



You can use GSM library to test, https://github.com/Microduino/Microduino_Tutorials/tree/master/Microduino_Libraries/_03_Microduino_GSM_SIM800L

Note:This library only supports Microduino-core.


Send short messages using the example program.


  • Hardware:Microduino FT232R, Microduino Core, Microduino GSM, USB cable or lithium battery;
  • Software: GSM library, Arduino IDE (version 1.0.3 and higher);
  • Uncompressed the zip folder to libraries of Arduino IDE;
  • Connect the Microduino FT232R and PC using USB cable to download program and monitor the serial port;
  • USB cable or li-ion battery to charge the Microduino GSM module and press the power button for a long time to activate Microduino GSM for about 4 seconds. That the power-on indicator goes on shows a successful start.


  • Download the test program:


  • Open the test program, and then you need double check the following parameter:
    • “#define NUM "13667928xxx"”:Need change to the number that receive message.
    • “#define SMS_CEN "13010720xxx"”:Your message center for you own mobile phone number, you can find it in your phone. It isn't the necessary. If hit an issue during send a message, you can try it.
  • Compile the program, select the board type "Microduino Core+ (Atmega644P@16M,5V)", download directly:
  • Open the serial monitor, set the baud rate is 9600:
    • Input "t", to send the message "wiki.microduino.cc";
    • Input "d", you can make a call, but can't finish a normal call, because no the speaker and microphone;
    • Input "h", you can submit a HTTP request to get some data from network;
    • Input "s", you can send the sensor data to network.
  • 如果你使用Microduino Core调试,你需要用到软串口(TX1,RX1)
  • If you use the Microduino Core to debug, must use the Software Serail (TX1,RX1)
    • Use the Software Serial library
#include <SoftwareSerial.h>

SoftwareSerial mySerial(2, 3); // RX, TX
    • Change the Serial1 to mySerial, it should be ok。
  • If you use the Microduino CoreUSB to debug, you only need to change the serial to serial 0 (TX0,RX0).


  • Does this module can be used to make a voice phone? Any voice pin was picked out?
    • This module can’t be made a voice phone, because it doesn’t have pin.
  • Does this module can work with Core+ module?
    • Yes.
  • Does this module can use Arduino GSM library?
    • Yes.
  • Does this module can use to 3G?
    • No, it only supports GPRS and GSM.
  • How to power on this module?
    • There are two methods:
      • Using the USB on attached module to supply the power, the voltage is 5V and the current MUST lager than 1A.
      • Using Li-ion battery on attached module to supply the power, the Li-ion should be 3.7V.

BM module can power on the Core module and other module, such as 10DOF, but don't suggest to power GPRS/GSM module, because it is a big power consumption module.




Microduino-GPRS/GSM Front
Microduino-GPRS/GSM Front
Microduino-GPRS/GSM Front
Microduino-GPRS/GSM Front