Specification: Origin: Mainland China Type: Module Condition: New Supply Voltage: +4.5-5.5 V Model Number: Dot Matrix Module Input voltage: +4.5-5.5V Input type: digital signal Interface terminal: XH2.54x4 Pin definition: G-ground V-power supply D(SDA)-serial data C(SCL)-serial clock Size: 31mmx31mmx14mm/1.22x1.22x0.55inch 1. The module is an 8*8 red light dot matrix driven by HT16K33. 2. The communication type is I2C, which can be connected to for arduino and other microcontrollers 3. The data communication interface of the module is I2C. As long as the microcontroller has this interface, it can be controlled. The specific implementation needs to be written by yourself. 4. When the address of multiple I2C devices conflicts, you can set the I2C address through A0, A1, and A2 on the connection board. The default address of the module is 0X70. Note: Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you! Please allow 1-2cm measuring deviation due to manual measurement. Included: 1 x  Dot Matrix Module