R
Hi,
I am the process of creating an application where PC sends commands to a Allen Bradley PLC and PLC sends feedback to PC. It is a rs-232 communication between the PC & the PLC. I am using Channel 0 on the PLC and COM1 on PC. On the PC side it's visual basic mscomm control that sends and receives infomatiom. On the PLC side I am using ASCII read and ASCII write instrucations to get/send infomation.
Problem that I am have is with ASCII write instruction. I am getting a right command to the PLC from the PC, but I am not getting the right feedback to the PC. I kind of figured out what the problem is: It looks like that what ever ASCII characters that being sent to the PLC, are also coming back to the PC again (even if I take off any ASCII write instruction from the ladder logic) how is this possible? Can anyone tell me why is this happening and how can I prevent it? Is there any special setup I need to do in ch0 config.?
Thanks for your help in advance!
-Ram
I am the process of creating an application where PC sends commands to a Allen Bradley PLC and PLC sends feedback to PC. It is a rs-232 communication between the PC & the PLC. I am using Channel 0 on the PLC and COM1 on PC. On the PC side it's visual basic mscomm control that sends and receives infomatiom. On the PLC side I am using ASCII read and ASCII write instrucations to get/send infomation.
Problem that I am have is with ASCII write instruction. I am getting a right command to the PLC from the PC, but I am not getting the right feedback to the PC. I kind of figured out what the problem is: It looks like that what ever ASCII characters that being sent to the PLC, are also coming back to the PC again (even if I take off any ASCII write instruction from the ladder logic) how is this possible? Can anyone tell me why is this happening and how can I prevent it? Is there any special setup I need to do in ch0 config.?
Thanks for your help in advance!
-Ram