Structured Text; Function Block - Allen-Bradley Logix5000 Reference Manual

Chapter 3 Timer and Counter Instructions (TON, TOF, RTO, TONR, TOFR, RTOR, CTU, CTD, CTUD, RES)
136
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

Rockwell Automation Publication 1756-RM003N-EN-P - October 2011