Indexed register issue SLC5/5 to Compactlogix conversion

Hello,

I'm running into an issue with how to resolve an indexed data array ADD in a SLC 5/5 to a Compactlogix 1769 L33ER conversion process.

I get a PCE error on the rung as "invalid expression or tag." I vaguely follow what's going on in the SLC. It's sampling a flow every certain seconds and adding to that index. I'm looking for suggestions on an easy way(or any way) to translate this to the compactlogix.

I get that the F (F33 0-256) is the array file of samples. [N7:7]:[N7:6] where 7 is the file index and 6 is the index counter.

Attached are the SLC and Compactlogix rungs top and bottom respectively.

Any ideas from you all out there is really appreciated!

In the Compact Logix, wouldn't you have to change the address to

F[N7_7].[N7_6]

or maybe you have to create F33 with 255 elements and an F34 with 255 elements and then write the tag as F33[N7_6] and F34[N7_6], respectively.

Check this thread Post #7 is similar to your request adding values of a 5 minute period.

http://www.plctalk.net/qanda/showthread.php?t=122828

you must first cerate an integer array tag "N7[512]
then you can copy the data into it the addressing format is different
when you copy a Float type to and integer type each float word will take 2 integers on the copy command.

Would this not work?
I've not done too much with respect to arrays, I also find the conversion tool causes more problems than its worth (would'nt use it myself).


The n7[7] and n7[6] arrays need to be increased to suit, the 'file and index' are aliased to the n7[7] and n7[6] arrays respectively and the source1 and 2 are REALS.


I can't try it out as I don't have access to a plc at the moment so I may be shooting in the dark.


Forgot to add source1 should be aliased to f8[16]



Steve

N7 would be an integer array
N7[6] - N7[7] are indexed elements of the same array
I assume that Sourc1 and Source 2 are both integers as well
data type is important as to how they are handled
I would need to see the ladder code
I knw the conversions are not very good I ran into that years ago converting a PLC2 to a PLC5 when they first came out I spent about 2 weeks chasing down and fixing the conversion errors

No source1 & 2 would be reals the n7 array would be type INT, the result I invisaged would be (if translated back to Logix500) the equivalent of F[n7:7]:[n7:6]



Steve

you could use reals as an index best practice an index should be integer
array N7 element 6 would hold the hole number of the result and N7element 7 would hold the decimal part of the number.
the copy used 2 consecutive elements in the array
A real 123.456 would be N7[6] = 123 and N7[7] would be 456
this is why if possible you should never mix data types

See attached file

Index_1 = N7:7 int must be less than 256
Index_2 = N7:6 int must be less than 256
Table = Real two dimension ( 256, 256)