A small Arduino library for GSM modules, that just works.

If you like TinyGSM - give it a star, or fork it and contribute!

Arduino Client interface support

This library is easy to integrate with lots of sketches, which use Ethernet or WiFi.
Examples for PubSubClient (MQTT), Blynk, Web Client and File Download are provided.

TinyGSM is tiny

WebClient example for Arduino Nano (with Software Serial) takes little resources:

Sketch uses 13,802 bytes (44%) of program storage space. Maximum is 30,720 bytes.
Global variables use 661 bytes (32%) of dynamic memory. Maximum is 2,048 bytes.

Now, you have more space for your experiments.

Supported modem models

• SIMCom SIM800 series (SIM800A, SIM800C, SIM800L, SIM800H, SIM808, SIM868)
• SIMCom SIM900 series (SIM900A, SIM900D, SIM908, SIM968)

Supported modules

• GPRSbee
• Microduino GSM
• Adafruit FONA (Mini Cellular GSM Breakout)
• Adafruit FONA 800/808 Shield

More modems may be supported later:

• Neoway M590
• AI-Thinker A6, A6C, A7
• Quectel M10, M95, UG95
• SIMCom SIM5320, SIM5216
• Telit GL865
• ZTE MG2639

Watch this repo for new updates! And of course, contributions are welcome ;)

Uses internal modem buffer for receive

TinyGSM pulls data gently from the modem (whenever possible), so it can operate on very little RAM.

Getting Started

1. Using your phone: - Disable PIN code on the SIM card - Check your ballance - Check that APN,User,Pass are correct and you have internet
2. Ensure the SIM card is correctly inserted into the module
3. Provide a good, stable power supply (up to 2A, 4.0-4.2V or 5V according to your module documentation)
4. Check if serial connection is working (Hardware Serial is recommended)
   Send an AT command using this sketch
5. Check if GSM antenna is attached

Troubleshooting

SoftwareSerial problems

When using SoftwareSerial (on Uno, Nano, etc), the speed 115200 may not work.
Try selecting 57600, 38400, or even lower - the one that works best for you.
Be sure to set correct TX/RX pins in the sketch.

Diagnostics sketch

Use this sketch to diagnose your SIM card and GPRS connection:
File -> Examples -> TynyGSM -> tools -> Diagnostics

Broken initial configuration

Sometimes (especially if you played with AT comands), your module configuration may become invalid.
This may result in problems such as:

• Can't connect to the GPRS network
• Can't connect to the server
• Sent/recieved data contains invalid bytes
• etc.

To return module to Factory Defaults, use this sketch:
File -> Examples -> TynyGSM -> tools -> FactoryReset

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License

This project is released under The GNU Lesser General Public License (LGPL-3.0)