Diagrammatic overview of worked example
All PLCs use standard communications settings (9600baud, 7 data, even parity, 2 stop bits). However, the host link unit numbers (contacts) must be set uniquely (use CX-Programmer, see below).
Connecting from PC to K3SC
Connection on RS422 network from master (K3SC) to slaves (CPM2A + CPM1-CIF11)
Switch settings for K3SC
All DIP SW settings should be set to off (default host link communications) except DIP SW 9
Switch settings details for other settings than default on K3SC.
Settings for Host Link ports within CPM2A (using CX-Programmer)
Settings for first CPM2A (With Host Link Unit 00)
Settings for second CPM2A (With Host Link Unit 01)
Once the PLC settings have been downloaded to the respective PLCs, then CX-Programmer can be used to communicate to both PLCs upon the RS422 network simultaneously. Make sure that the settings for communication are set to reflect the Host Link unit addresses set and downloaded above.
CX-Programmer showing PLC instances (2 PLC’s set in the project)
Host Link communication settings for ‘PLC_Host_00’
Host Link communication settings for ‘PLC_Host_01’