Features: 15V, 3V compatible design, suitable for 5V and 3V chip work, commonly used STC series and AVR microcontrollers can be used to meet the needs of different users. 2The development board has 8 SMD LED lights, 6 SMD buttons, 4 LED digital tubes. 3The buzzer has sound prompts, and can be used for music, alarm, etc. experiments. 4Serial port conversion chip MAX3232, which supports both 5V and 3.3V voltage, can realize serial communication, STC single?chip programming and other functions. 5The temperature sensor DS18B20 interface and infrared receiving interface can be used for infrared receiving experiments such as H1838, which can realize infrared remote control keyboard expansion. 6The ISP interface is the interface for AT/AVR microcontroller to download programs, and can be equipped with a corresponding USB-ISP downloader. 7Mini USB power supply and external stabilized power supply, onboard 3.3V stabilized power supply chip. 85V and 3.3V power selection switch, expand the scope of use, and on?board devices can work normally within 5V and 3.3V. 9Out all IO ports for easy operation and expansion of external devices, 3.3V and 5V power supply expansion interface, can provide power for external devices. Package included: 1 x Development Board 1 x USB Data Cable