Siemens SIMATIC S7-1200 Reference Manual page 11

Basic instructions
✔ ✔ ✔ ✔
Scan Boolean result for positive signal edge
✔ ✔ ✔ ✔
Scan Boolean result for negative signal edge
Detect positive signal edge
SCL: Programming with two instructions is
more effective:
✔ ✔
posFlanke := signal and not
laststate;
laststate := signal;
Detect negative signal edge
SCL: Programming with two instructions is
more effective:
✔ ✔
negFlanke := not signal and not
laststate;
laststate := not signal;
✔ ✔ ✔ ✔
Normally open contact
✔ ✔ ✔ ✔
Normally closed contact
A5E33284667-AA
Extended instructions
Description
Technology
LAD/FBD
(not S7-1200)
P_TRIG
N_TRIG
R_TRIG
F_TRIG
-||- nn
-|/|- nn
Communication
STL
SCL
FP nn
FN nn
nn nn
nn nn
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