用单片机的C语言编的键盘递增递减的C程序的源代码（按一下键，对应的键值增或减一），在很多领域用到此思想，如空调调温等，可供单片机开发工程师参考。-the MCU series of the C language keyboard incremental decrease in C program's source code (by pushing a button, the corresponding increase or decrease of the pair a), used in many areas here thinking, such as air-conditioning thermostat, MCU development engineers for reference.