Siemens SIMATIC S7-1200 - Page 11

A5E33284667-AA Page 10
Extended instructions
Basic instructions
Communication
Technology
S7-300
S7-400
S7-1200 S7-1500
Description LAD/FBD
STL
(not S7-1200)
SCL
✔
✔
✔
✔
Scan Boolean result for positive signal edge
P_TRIG
FP
nn
✔
✔
✔
✔
Scan Boolean result for negative signal edge
N_TRIG
FN
nn
✔ ✔
Detect
positive signal edge
SCL: Programming with two instructions is
more effective:
posFlanke := signal and not
laststate;
laststate := signal;
R_TRIG
✔ ✔
Detect negative signal edge
SCL: Programming with two instructions is
more effective:
negFlanke := not
signal and not
laststate;
laststate := not signal;
F_TRIG
✔
✔
✔
✔
Normally open contact
-||-
nn
nn
nn
✔
✔
✔
✔
Normally closed contact
-|/|-
nn
nn
nn