MikeVT
Lifetime Supporting Member
Good Morning!
I need to monitor ethernet comms, between 2 Compact Logix PLC's. I have done this before with a simple pair of timers, toggling a bit (on the sending side) and a timer monitoring a bit on the receiving side.
However, This is the 'spec' I'm dealing with, from an equipment vendor, regarding a DINT being monitored as a comms watchdog.
"[FONT="]This value must continuously increment by 1 at every CPU cycle. When reach the Data Type max value, restart from 0. If the increment stops means that there is a PLC or a communication error."
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[FONT="]I have not used, or seen an example of the logic needed to monitor comms this way. I am asking for some examples of ladder logic, to accomplish this, please.[/FONT]
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[FONT="]Thank you!
[/FONT]
I need to monitor ethernet comms, between 2 Compact Logix PLC's. I have done this before with a simple pair of timers, toggling a bit (on the sending side) and a timer monitoring a bit on the receiving side.
However, This is the 'spec' I'm dealing with, from an equipment vendor, regarding a DINT being monitored as a comms watchdog.
"[FONT="]This value must continuously increment by 1 at every CPU cycle. When reach the Data Type max value, restart from 0. If the increment stops means that there is a PLC or a communication error."
[/FONT]
[FONT="]
[/FONT]
[FONT="]I have not used, or seen an example of the logic needed to monitor comms this way. I am asking for some examples of ladder logic, to accomplish this, please.[/FONT]
[FONT="]
[/FONT]
[FONT="]Thank you!
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