Design and Research of Microcontroller I/O Control Technology

This paper designs a new control system architecture of the Internet of things(IoT), which enables controlling the I/O interface of a microcontroller unit(MCU) via smartphone based on the WebUSB technology. Firstly, an I/O control protocol of the MCU is designed based on WebUSB, so as to standardize the function calls of various I/O procedures; Secondly, based on the WebUSB programming interface, the host side of this I/O control protocol is designed and implemented on the browser side to control the MCU; Then, the device side of the I/O control protocol is implemented based on the USB peripheral stack in the MCU to complete the response and execution of control commands; Finally, a hardware function verification platform based on STM32F103 Series MCU is built, which utilizes the hardware interface to connect to a servo steering gear, and uses the USB interface to receive commands from the PC or smartphone. Through browser based software development, it calls the PC or smartphone’s on-device camera to detect the position of a human face, and uses the MCU I/O to control servo rotation so as to realize automatic face tracking.