Allen-Bradley Logix5000 Reference Manual page 163

Condition
EnableIn is set.
Instruction execution
.EW Bit = 1
.ST Bit = 1
.DN Bit = 1
.ER Bit = 1
Relay Ladder Action
N/A
.EN Bit = 1
Examine .EW Bit
.EW Bit = 0
Examine .ST Bit
.ST Bit = 0
Examine .DN Bit
.DN bit = 0
.ER Bit = 0
Examine .ER bit.
.EW, .ST, .TO, .DN, and .ER bits are cleared.
.EN bit is set.
Execute message request.
.EW bit is set.
Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Input/Output Instructions (MSG, GSV, SSV, IOT)
Structured Text Action
EnableIn is always set.
The instruction executes.
.EN Bit = 0
Examine .EN Bit
Examine .EW Bit
Examine .ST Bit
.EW, .ST, .TO, .DN, and .ER Bits are
cleared.
.EN bit is set.
Yes
Block-transfer
Command
No
Yes
.ER bit is set.
Rung-condition-out is
set to false.
.EW bit = 1
.EW Bit = 0
.ST Bit =
.ST Bit = 0
.EN bit is set.
No
Module Path Valid
Yes
Module
No
Connection
Running
End
Chapter 4
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