A study on the user-defined reliable communication protocol in on-machine verification system

In order to realize the on-machine verification of CNC, both the uploading of the verification programs generated in user's computer to CNC and the downloading of the verification results from CNC to user's computer are badly needed for the subsequent modules in on-machine verification system. In light of serial port RS232's universal application, the author would do in-depth research on the serial port file transfer between PC and CNC. Moreover, a user-defined serial port transfer protocol is proposed on the basis of serial port communication protocol. In order to guarantee the reliable of file transmission, file is transferred as packet and cyclic redundancy check is introduced as the coding mode of channels. With Windows API and multithread technology, serial port file transfer software is realized at VC++ platform.