【摘要】 为了适应嵌入式设备外设的多样性,本文以特殊矩阵键盘为例,设计了一套完整的驱动控制模块。硬件电路设计采用外扩3片SN74HC164芯片的方式,节省了GPIO引脚的使用,大大提高了利用效率。同时,在此基础上引出了Linux内核中input子系统的特性和工作机制,呈现了较为完整的输入事件由内核空间传递到用户空间进程的过程。实验结果表明,设计的驱动模块具有良好的实时性和准确性。更多还原

【Abstract】 In order to adapt the diversity of embedded device peripheral,this paper takes special matrix keyboard as an example,and a complete set of drive control module is designed.Hardware circuit design takes 3 expanding SN74HC164 chips to save the GPIO pins,and it greatly improves the utilization efficiency.Meanwhile,on the basis it leads to the characteristics and working mechanism of input subsystem in Linux kernel,presenting a complete process of input events from kernel space to user space.The experimental results show that,the driving module has good performance in real-time and accuracy.更多还原