1.Digital I/O There are 0~13 digital input and output terminals. 2. Analog I/O analog input and output terminals are 0~5. 3. Input voltage: No external power supply is required when connecting to the computer USB, and the external power supply is 5V~9V DC voltage input. 4. Output voltage: 5V DC voltage output and 3.3V DC voltage output. Controller: ATMEGA328P Analog input pins: 6 (2 of which can be used as I2C interface) Digital IO: 14 (6 of which can be used as PWM ports) Flash memory capacity: 32KB (of which 2KB has been used as Bootloader space) USB supply voltage: 5V Static memory: 2KB External power supply voltage (recommended value): 7~12 EEPROM: 1KB Maximum current of external power supply: 1A Clock frequency: 16MHz IO port maximum current: 40mA Working voltage: 5V Dimensions: 75 x 54 x 15mm Colour:blue Material:plastic Size: 75 x 54 x 15mm Package Contents: 1 x Development Board 1 x Cable Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.