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136 Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Chapter 3 Timer and Counter Instructions (TON, TOF, RTO, TONR, TOFR, RTOR, CTU, CTD, CTUD, RES)
Example: Each scan after limit_switch1 is cleared, the TOFR instruction increments the
ACC value by elapsed time until the ACC value reaches the PRE value. When
ACC ≥ PRE, the DN parameter is cleared, and timer_state2 is set.
Structured Text
TOFR_01.Preset := 500
TOFR_01.Reset := reset;
TOFR_O1.TimerEnable := limit_switch1;
TOFR(TOFR_01);
timer_state2 := TOFR_01.DN;
Function Block