In order to provide an inexpensive entry point to evaluation, prototyping and developing use the TB-S3A1 Target Board Kit that provides pin headers that allow access to all MCU signals, as well as a number of on-board peripherals. The target board features Segger J-Link-OB debugger on board, Full-Speed USB 2.0 Device port, Main power input of 5 V from Debug USB connector, optional 3.3 V from header pins, a 32.768 kHz RTCC crystal and 12 MHz MCU clock crystal, User LED and buttons (Cap Touch and mechanical), Reset button and Status LEDs, 10-pin header for optional external debug probe connection, and MCU boot configuration jumper.