ControlLogix L73 (RSLogix5000): Mode Decoder?

Join Date
Dec 2016
Location
Southeast
Posts
134
This app has multiple modes which control different combinations of pumps, valves, instruments, etc. I'd like to do this using bit control. What's the best way? Is there a built-in programmable "ModeDecoder" I can use, or do I have to code it all out in brutalized logic?
 
Hint ...

CLR ModeBits
OTE ModeBits.[ModeNumber]

Indirect Addressing
 
If brute force logic is clearer, then I use brute force logic.

I'd rather have a set of a dozen rungs that literally looked like a truth table than a clever indirect addressing rung.
 
If brute force logic is clearer, then I use brute force logic.

I'd rather have a set of a dozen rungs that literally looked like a truth table than a clever indirect addressing rung.

Each to their own, Ken. I don't think indirect addressing is "clever", nor is it difficult to understand.

Most Bubbas worth employing understand a number inside square brackets that specify an array element, so it's not a great leap for them to understand how a tag name or an expression inside the brackets can be evaluated down to the array element number.

If indirection allows me to write one rung of code instead of n rungs of code, then I'll use, and teach, the least "expensive" method, in terms of memory usage, and execution time.

In another thread, the OP posted an application that decodes a two-digit thumbwheel switch using eight inputs.... it was done "brute-force" with 20 rungs of code, 10 for each decade, then the 2 partial results had to be added together to form the result. I resisted the temptation to shout FRD !
 

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