1、ps/2键盘输入，通过led显示ascii码

2、稍等1s可以在lcd上显示输入的字符

3、其中键盘上的backspce键是用来清屏的

4、当lcd上显示满字符时，在按下按键自动清屏，从第一行显示-1, ps/2 keyboard input, through the led display ascii code 2, wait 1s in the lcd display characters input 3, which backspce keys on the keyboard was required to settle the screen 4, when the full character lcd display, the Press the button in the Auto-ching screen, from the first line of display