Rockwell Automation 1761-HHP-B30 MicroLogix 1000 with Hand-Held Programmer (HHP) - Manual (Page 247)

Chapter 13
Using Application Specific Instructions
13–21
Ladder Rungs
Rung 4:0
Resets the hole count sequencers each time the low preset is reached. The
low preset has been set to zero to cause an interrupt to occur each time
that a reset occurs. The low preset is reached anytime that a reset C5:0
or hardware reset occurs. This ensures that the first preset value is
loaded into the HSC at each entry into the RRUN mode and each time that
the external reset signal is activated.
| interrupt 3 hole |
| occurred preset |
| due to sequencer |
| low preset |
| reached |
| +INT––––––––––––––––––––+ C5:0 R6:4 |
|–+INTERRUPT SUBROUTINE +––––] [–––––––––––––––––––––+–––(RES)––––+–|
| +–––––––––––––––––––––––+ IL | | |
| | 5 hole | |
| | preset | |
| | sequencer | |
| | R6:5 | |
| +–––(RES)––––+ |
| | | |
| | 7 hole | |
| | preset | |
| | sequencer | |
| | R6:6 | |
| +–––(RES)––––+ |
| |
Rung 4:1
➀
Keeps track of the hole number that is being drilled and loads the correct
HSC preset based on the hole count. This rung is only active when the
”hole selector switch” is in the ”3–hole” position. The sequencer uses
step 0 as a null step upon reset. It uses the last step as a ”go forever”
in anticipation of the ”end of manual” hard-wired external reset.
| hole |hole 3 hole |
| selector |selector preset |
| switch |switch sequencer |
| bit 0 |bit 1 |
| I:0 I:0 +SQO–––––––––––––––+ |
|––––]/[––––––––] [–––––––––––––––––––––+–+SEQUENCER OUTPUT +–(EN)–+–|
| 9 10 | |File #N7:50+–(DN) | |
| | |Mask FFFF| | |
| | |Dest N7:7| | |
| | |Control R6:4| | |
| | |Length 5| | |
| | |Position 0| | |
| | +––––––––––––––––––+ | |
| | | |
| | force the | |
| | sequencer | |
| | to increment | |
| | on next scan | |
| | R6:4 | |
| +––––(U)––––––––––––––––––––+ |
| EN |
➀
This rung accesses I/O only available with 32 I/O controllers. Therefore, do not include this rung if you are using a 16
I/O controller.