Step7 Detecting Positive Edge In SCL
- Thread starter mosama
- Start date
Dont think there is a one-shot block for SCL.
But it is trivial to code.
signal_oneshot_ON := signal_input AND NOT signal_mem ; // generate the ON oneshot
signal_oneshot_OFF := NOT signal_input AND signal_mem ; // generate the OFF oneshot
signal_mem := signal_input ; store the status of the input
But it is trivial to code.
signal_oneshot_ON := signal_input AND NOT signal_mem ; // generate the ON oneshot
signal_oneshot_OFF := NOT signal_input AND signal_mem ; // generate the OFF oneshot
signal_mem := signal_input ; store the status of the input
Unfortunately, I have no experience with Unity Pro.
STEP7 is coming in a completely new version (v11) which includes a much-improved SCL.
Apart from that, Siemens SCL should be equivalent to Structured Text in IEC61131-3. Dont know if there is a oneshot standard function in IEC ST.
STEP7 is coming in a completely new version (v11) which includes a much-improved SCL.
Apart from that, Siemens SCL should be equivalent to Structured Text in IEC61131-3. Dont know if there is a oneshot standard function in IEC ST.
TurpoUrpo
Lifetime Supporting Member
The editor is LOT better. Have not tested debug yet. But there is actually working autocompletion.
Yes in Structured Text there is "RE" (rising edge) instruction, but it only works with EBOOL data type.
Also Unity Pro Structured Text editor doesn't need compilation in order to see the errors. The errors appears while you are programming by drawing a red line under the error.
I think SCL have the advantage of defining variables from the source code, and this not found in Unity Pro Structured Text.
Like I said, I dont know Unity Pro.
But, I think that what mosama and GeoffC calls "defining variables" are two different things.
In S7 SCL (and the other languages) you create UDTs, DBs, FCs and FBs wherein you have variable declarations.
In Unity Pro ST, you can create a global variable via a shortcut function without leaving the editor (at least thats what I figure out from GeoffC's input).
But, I think that what mosama and GeoffC calls "defining variables" are two different things.
In S7 SCL (and the other languages) you create UDTs, DBs, FCs and FBs wherein you have variable declarations.
In Unity Pro ST, you can create a global variable via a shortcut function without leaving the editor (at least thats what I figure out from GeoffC's input).
I mean that in Step7 you may declare variables directly from the code like this:
VAR X1, X2, X3:BOOL; END_VAR
But you can't do this in Unity Pro
Yes but these instructions needs two parameters: ClockInput & Output, but "RE" and "FE" only needs one parameter and works only with EBOOL data type.
My regards
Last edited:
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