Rockwell Automation 1772-L8_LW_LWP_LX_LXP,D17726.5.8 User Manual - Manual (Page 391)

Chapter
25
25-1
Programming Techniques
This chapter describes several programming techniques:
one-shot programming
re-start
cascading
timers
temperature conversions
program control
The one-shot programming technique sets a bit for one program scan only.
There are two types of one-shots:
leading edge
trailing edge
Leading Edge One Shot
A leading edge one-shot sets a bit for one scan when its input condition has
made a false-to-true transition. The false-to-true transition represents the
leading edge of the input pulse (Figure 25.1).
Figure 25.1
Leading Edge One Shot
112
04
011
14
253
00
253
00
112
04
253
00
L
011
14
U
011
14
010
00
Chapter Objectives
OneĆShot Programming