Modbus ASCII及LRC校验程序代码。-Modbus ASCII and LRC check code.

自己写的一个modbus小程序，支持rtu和ascii方式，其原理是采用注册解析回调函数的方式实现的。-Modbus wrote a small program to support rtu and ascii mode, the principle is the use of registered callback function analytic approach to achieve.