Question in regard to the serial port on the M340 PLC


Thread Starter



I would like to know how to flush the serial buffers on the M340 PLC. I have noticed that on the serial port sometimes values tend to become stagnant. I am using the read_var block to get data from a remote instrument. Whenever I rebuild my program and load it to the PLC I get the correct values. I tried flushing the integer receive buffer array (output pin of read_var block) once every 10 sec without success.

Also I would like to know what exactly happens to the serial port when a program is loaded to the M340 PLC? Apart from clearing the communication counters what other buffer registers get flushed? Are there any internal registers of the read_var block accessible so that they could be flushed?

I have even tried cycling power to the instrument without success.

I would appreciate it, if someone could suggest me a solution.

Best Regards,