arm linux 3x4的矩阵键盘驱动-arm linux 3x4 matrix keyboard driver

汇编程序的矩阵键盘识别程序，通过设置键盘的行与列，继而进行扫描，识别3x4共12个按键！-Assembler matrix keyboard recognition program, by setting the keyboard rows and columns, and then scanned to identify a total of 12 keys 3x4!

设计一个3X4键盘，输入按键的数字并显示出来-Design of a 3X4 keyboard, numeric input keys and displayed