这是一个MODBUS协议的串口接收和发送程序，其特点在于采用了中断接收方式，边接收边进行MODBUS协议常用功能的检查（如其3、5、6、16号），并根据MODBUS协议，设置了后门，可以方便厂家在维护时的便利-This is a MODBUS protocol serial port receive and transmit procedure is characterized by the use of the interrupt reception mode while receiving side to carry out common functions MODBUS protocol inspection (as No. 3,5,6,16), and in accordance with MODBUS protocol, set up the back door, it will be convenient when manufacturers in the maintenance of facilities