What is the operational difference between these two FBD items
- Thread starter mister x
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drbitboy
Lifetime Supporting Member
no change in the output, of course.
Is it possible that with the Block you have access to the most recent state of [BNOT_02.In] elsewhere in the program, while the input itself (bool_in_1) could be a temporary variable and changed by other parts of the program after the BNOT_02 Block IS evaluated? E.g. bool_in_1 could be used to keep track of some state that changes throughout the program and be latched and/or unlatched at several points throughout.
That is not so much an operational difference, but it would make it more convenient to display, on an HMI, the state of the program at the time BNOT_02 was evaluated.
I make this as a suggestion for why might be done that way, but it would seem to be a poor practice, as well as unlikely to be necessary in these days of relatively unrestricted memory capacity.
Is it possible that with the Block you have access to the most recent state of [BNOT_02.In] elsewhere in the program, while the input itself (bool_in_1) could be a temporary variable and changed by other parts of the program after the BNOT_02 Block IS evaluated? E.g. bool_in_1 could be used to keep track of some state that changes throughout the program and be latched and/or unlatched at several points throughout.
That is not so much an operational difference, but it would make it more convenient to display, on an HMI, the state of the program at the time BNOT_02 was evaluated.
I make this as a suggestion for why might be done that way, but it would seem to be a poor practice, as well as unlikely to be necessary in these days of relatively unrestricted memory capacity.
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