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

Page 304

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Chapter 15
Using Communication Protocols

15–20

Rung 2:3
This rung monitors the message instruction for “Done” conditions. When
both messages are done, both messages are reset, allowing the sequence to
be restarted in the next scan. The error retry bit is also used to reset
both messages if an error or lockup condition is encountered.

| Read Message Write Message Write Message |
| Done Done Enabled |
| N7:60 N7:50 N7:50 |
|–+––––] [––––––––––] [–––+––––––––––––––––––––––+––––(U)––––––––––+––|
| | 13 13 | | 15 | |
| | Message Error | | Read Message | |
| | Retry Timer | | Enabled | |
| | T4:9 | | N7:60 | |
| +––––] [––––––––––––––––+ +––––(U)––––––––––+ |
| DN 15 |

Rung 2.5

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|–––––––––––––––––––––––––––––––––––––+END+–––––––––––––––––––––––––––|
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