micro800 series - ModbusTCP

Hi Team,
what is the best way to handle multiple slaves when using a m800 series as a master.
I read that a maximum of 4x instructions can be processed per scan, but what to do when there are more than 4?

In the micrologix, we can use the .DN/ER bits to advance/increment etc, but the .Q flag cannot be used in the same way as it remains high even when the .IN is low AND will make the logic to right of the rung true
(I just don't get why some manufacturers have done this )

Sure, we can use a timer & step routine to make each instance exclusive but what is the trigger for incrementing?
I guess if a short timeout was used, then this could be the incrementing interval. Not ideal, but would work.


LC

It’s been a long time since I’ve done any messaging in CCW and I don’t recall having a problem using the Q bit as the trigger for the next instruction. However it has been a long time so I really don’t know. You could try using a timer to trigger a counter at a given time frame (500ms?). When the counter’s accumulator equals 1, trigger one set of message instructions. When the counter’s accumulator equals 2, trigger the next set of message instructions and so on. When you hit the last set of message instructions, use a reset to move the counter back to 0.
Just my thought.