hd7279a 驱动程序,实现对4位数码管的时间显示-hd7279a driver, to achieve four digits of the time display

使用HD7279芯片，实现循环右移、闪烁等功能-Using the HD7279 chip, rotate right, flashing etc.

7279 键盘及led的显示利用HD7279A 控制键盘和显示，要求任意按下键，在LED 最右 位显示对应键号值，其余显示值左移一位。-Show utilize HD7279A 7279 and led the keyboard control keyboard and display, requiring any key is pressed, the LED rightmost Displays the corresponding key number, and the remain