Controllogix Arrays

[plcengineer]

I have a controllogix processor with a few boolean arrays set up.. For example, one array is Step_Cycle_Complete. Basically, the addressing goes from Step_Cycle_Complete[1] through Step_Cycle_Complete [150]. How can I write zeroes to all these addresses at once. I don't want to put in unlatch coils for every address..

Thanks,

 

[Hundikoer]

FLL instruction should work for that

Also you can use indirect addressing and create a loop, where you unlatch every sequence Step_Cycle_Complete[index+1]

Regards
Lauri

 

[Gerry]

FLL instruction should work for that

No it won't.

However, you can create a UDT to contain the boolean array and use FLL on the tag of the UDT type (length 1).

e.g.
create a UDT called "XYZ" containg a single boolean array called Complete[160].
Create a tag "Step_Cycle" of type "XYZ"
Now you can address the bits individually as Step_Cycle.Complete[x] where x is 0 to 159
To clear all the bits you can use FLL with source = 0, destination = Step_Cycle, and length = 1.

PS I chose length 160 to align it to a DINT boundary.

 

[plcengineer]

I tried the FLL with my current setup and it wouldn't work. I would like to try the UDT tag but I am not familiar with how to do this. Please give some insight on the UDT tag and how to make the system that I need to clear all bits with one FLL instruction..


Thanks,

 

[Hundikoer]

Yep Gerry, I used also UDT. It is so common in RSL5K that I did not bother to mention it.

So, I used similar approach just yesterday.

1) Create UDT, by opening "Data Types" folder in Program tree (or however they call it)
2) Right click on "User-Define" and select "New Data Type"
3) Give name for your data type (I my excample it was ValveErrors)
4) Add member(s) for your new data type (I added "ValveClosed" and "ValveOpen", bot BOOL type). Save
5) Then edit controller (or program) tags. Add new tag (I used Valve_Errors) and define datatype (so it is in that case "ValveErrors")
6) Define also array (I used 64)

If you vant to clear all bits just "FLL 0 Valve_Errors[0] 50". 50 is number of members in this area you want to reset.

Hope it was little more precise description and I did not miss anything


BR
Lauri