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A Simple USB Keyboard to Realize One-Way Communication

The basic principles of USB peripheral interface of STM32 micro-controller is introduced, the main function of each file of the basic structure in standard peripheral library and USB firmware library are analyzed in this paper. The files of clock, interrupt, input/output are modified based on standard peripheral library of the STM32 micro-controller and examples in the USB firmware library to realize the keyboard input function. A report descriptor of the simple USB keyboard is added to the USB firmware library. A simple USB keyboard is designed to effectively realize the one-way communication between the USB keyboard and the computer.