【摘要】 在PLC程序设计中,采用MOV指令进行数据传送,采用CMP指令进行数据比较,应用8个内部数据通道传送数据。PLC程序中所需参数均由VB程序输入。VB与PLC的通信采用HostLink通信协议,应用VB中的MSComm控件实现串口通信,通信参数设置为:波特率9600,偶校验,数据位7,停止位2。编写了Fcs校验函数、发送程序以及接收程序。PLC采用RS232C口与上位机的COM口进行通信,采用上位计算机监控PLC程序运行,并进行数据传输与处理。更多还原

【Abstract】 The data transmission and the data comparison are carried on by the MOV and CMP command respectively,and 8 internal data parameters are applied in the PLC procedure. The parameters needed by PLC procedure are input through VB procedure. The communication between VB and PLC adopts HOST LINK communicate protocal. The serial communication is relized by the MSComm control in VB. The communication parameters are set as follows: the baudrate 9600,the data position 7,the stop position 2. Then the FCS function is compiled to complish check,sending and recieving process procedures. PLC uses the RS232C port to carry on the correspondence with COM of top computer. the PLC procedur running is monitored by top computer,and carries out data transmission and processing.更多还原