Features: brand new and high quality 1, the board based on the most basic MCU circuit, 8M and 32768 crystal circuit, USB power supply circuit. 2, the core board is divided into two rows leads to all the I / O port. 3, with SWD simulation debug download interface, simple and convenient, debugging speed. 4, the use of the Mirco USB interface, you can do USB communication and power supply, USB interface, for the ordinary Andrews mobilephone charger interface. 6, Easy to start, more stable. Specifications: Chip : 32F103C8T6/ 32F103C6T6 (Optional) Core: ARM 32-bit Cortex-M3 CPU Size: approx 22.5mmx53mm / 0.88x2.09in Debug mode: SWD Number of pins: 48; Kernel: Cortex-M3; Operating frequency: 72MHz; Storage resources: 64K Byte Flash, 20KByte SRAM; Interface Resources: 2x SPI, 3x USART, 2x I2C, 1x CAN, 37x I / O ports, Analog-to-digital conversion: 2x ADC (12-bit / 16-channel) Timers: 3 general timers and 1 advanced timer Debug Download: Support JTAG / SWD debug interface to download, support for IAP. 2, RT9193: 3.3V regulator chip, the maximum output of 300mA. CHIP 32F103C6T6 Descriptions: Interface Description: 1, SWD interface: support for simulation, download and debug. 2, Mirco USB interface: power supply and USB communication, does not support the download. 3, USART1 interface: USART1 can be used to download the program, or use the USART1 for communication. 4, MCU pin interface: leads all I / O port pins, easy to connect with peripherals. 5, 5V and 3.3V power input and output interface: commonly used in external power supply, or with other modules for common ground treatment Package Includes: 1 PC x STM32F103 System Board note: Due to the problems of lighting effects and shooting angles, there will be certain tolerances in the product, please understand. Please allow 0-1cm error due to the manual measurment.