AlexDarsigny
Member
Hi,
I'm using Control Expert (a.k.a Unity Pro) to program M340 PLC. I am looking for a patch to fix what I think is a bug in PLC library.
Please look at this short video : https://www.youtube.com/watch?v=t2N1-RHJUWc
Basically, I have a working communication with a Modbus slave but if I close it, my M340 is not able to recover communication. In fact, READ_VAR block seems to be stuck in an infinite loop since EN output is never TRUE even if EN input is set to TRUE multiple times. Please note I'm using a PLC simulator, I'll confirm the behavious with a real PLC soon.
Re-starting PLC fix the problem obviously but that's not a solution.
The only solution I have is to use a second READ_VAR instance with different variable for GEST or it doesn't work. I could program 10 instances waiting for the previous one to fail but that's really not a good solution. I tried to play with everything attached to READ_VAR (especially GEST array) but couldn't find a viable solution.
Any ideas? Thanks!
I'm using Control Expert (a.k.a Unity Pro) to program M340 PLC. I am looking for a patch to fix what I think is a bug in PLC library.
Please look at this short video : https://www.youtube.com/watch?v=t2N1-RHJUWc
Basically, I have a working communication with a Modbus slave but if I close it, my M340 is not able to recover communication. In fact, READ_VAR block seems to be stuck in an infinite loop since EN output is never TRUE even if EN input is set to TRUE multiple times. Please note I'm using a PLC simulator, I'll confirm the behavious with a real PLC soon.
Re-starting PLC fix the problem obviously but that's not a solution.
The only solution I have is to use a second READ_VAR instance with different variable for GEST or it doesn't work. I could program 10 instances waiting for the previous one to fail but that's really not a good solution. I tried to play with everything attached to READ_VAR (especially GEST array) but couldn't find a viable solution.
Any ideas? Thanks!
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