MSG alternative to acees BOOL type data?

[Sergei Troizky 26]

Since the CIP MSG instruction supports only numerical data types, is there an alternative way to read/write booleans in Logix5000 processor?

Base boolean tags, not aliases to numerical data type tag bits.

[Michael Lloyd 85]

I'm not able to pull up Logix at the moment but you could map one format to another in structured text (there are other means but this lets you control what goes where with no regard to bit or byte order in the CIP tag). As a crude example:

CIPTag1 of the type INT mapped to BOOLTag1 of the type BOOL[16] <-- I actually don't think you can do an 16 bit array, I'm pretty sure it has to be be BOOL[32].

Depending on which way you are going:

CIPTag1.0 := BoolTag1.0;

CIPTag1.1 := BoolTag1.1;

etc...

or

BoolTag1.0 := CIPTag1.0;

BoolTag1.1 := CIPTag1.1;

etc...

[NevergoldMel 38]

Bit Packed Words

 

[Sergei Troizky 26]

The problem is that it should not require any preprogramming (program code, data type, aliasing, etc.) that refers specific tags.

The solution must be tag name- independent and work with any arbitrary BOOl tag created by the standard procedure.

[Michael Lloyd 85]

Logix 5000 is a tagname based environment. If there aren't any Boolean tags there aren't any Booleans

[Sergei Troizky 26]

Michael, I said any tag created by the standard procedure, so it exists.

But it is a base type BOOL tag, not an alias nor member of UDT.

[Michael Lloyd 85]

5 minutes ago, Sergei Troizky said:

Michael, I said any tag created by the standard procedure, so it exists.

But it is a base type BOOL tag, not an alias nor member of UDT.

Ok, then mapping the tag works (same thing as bit packing, just one at a time). Message to an INT, then assign the bits from the INT to the BOOL

[pcmccartney1 141]

An array of BOOLs?

[Sergei Troizky 26]

Michael, your suggestion violates the initial condition: reading a BOOL tag should not require in the target controller any preprogrammed procedure specific to the tag name.

pcmccartney1, the same, plus the MSG instruction still will not support boolean datatype, arrayed or not.

[Michael Lloyd 85]

Ok, then it’s easy, you can’t do that.