Hi!
It is always said, that DINT is the most performant datatype in AB plcs.
I while ago i made a performance test. Several instructions like ADD, SUB, EQU and so on in a loop repeated 50000 times.
The difference between the different datatypes was neglectable. (excepting operations with REAL types)
I made a second test, the same operations but without a loop. This time in Structured Text, each instruction copied a few thousand times. Also no noteworthy difference in cycle time.
But what i found out, the used program memory increased clearly.
The thing is, our main PLC platform is Siemens. In Siemens they use nearly all available datatypes depending on what fits best. Up to now, i always replaced everything with DINT when converting Siemens programs to AB. I was afraid of performance issues.
Has anybody ever thought about this or is everybody just using DINT`s?
It is always said, that DINT is the most performant datatype in AB plcs.
I while ago i made a performance test. Several instructions like ADD, SUB, EQU and so on in a loop repeated 50000 times.
The difference between the different datatypes was neglectable. (excepting operations with REAL types)
I made a second test, the same operations but without a loop. This time in Structured Text, each instruction copied a few thousand times. Also no noteworthy difference in cycle time.
But what i found out, the used program memory increased clearly.
The thing is, our main PLC platform is Siemens. In Siemens they use nearly all available datatypes depending on what fits best. Up to now, i always replaced everything with DINT when converting Siemens programs to AB. I was afraid of performance issues.
Has anybody ever thought about this or is everybody just using DINT`s?