程序作用：测试Sage Tech.开发板（MCP300）中hd7279键盘显示芯片是否能正常工作 */

/*程序功能：按下1号键显示0、1、2、3，按下2号键显示c、d、e、f，按下3号键显示4、5、6、7 */

/* 按下4号键显示8、9、a、b，按下0号键点亮4个LED灯 */ -procedures role : Sage Tech test. Development board (MCP300) hd7279 keyboard chip can show normal work * / / * functions of the program : Clicking on the 1st bond shows 0, 1, 2, 3, press the button on the 2nd show c, d, e, f, press the button on the 3rd show 4, 5, 6, 7 * / / * Press the button shows on the 4th 8,9, a, b, press the button to light up the 0, 4 LED lights * /