Rockwell Automation RECOMM-PBUS PROFIBUS Communications Module User Manual
Page 63
Using I/O Messaging
6-11
For Ladder 3 Station 1 Drive Logic, see figure 6.5, Sample SLC
Ladder - Station 1 Program.
For Ladder 4 Station 2 Drive Logic, see figure 6.6, Sample SLC
Ladder - Station 2 Program.
Figure 6.5 – Sample SLC Ladder Logic - Main Program (Continued)
PROFIBUS scanners vary from manufacturer to manufacturer in how the bytes are ordered in a word. For example, some PROFIBUS
scanners operate with high & low bytes swapped (the value "1234" is represented as "3412"). The READ data is copied into
N10: and the bytes are reversed in the SWP instruction below so a value such as "3412" is viewed as "1234".
0003
COP
Copy File
Source
#N9:0
Dest
#N10:0
Length
28
COP
Station 1
Logic Status
File N10: contains the actual read data that can be used elsewhere in the ladder program.
Station 1
Station 2
Description
M1:1.0
(N10:0)
M1:1.14
(N10:14)
Logic Status
M1:1.1
(N10:1)
M1:1.15
(N10:15)
Speed Feedback
M1:1.2
(N10:2)
M1:1.16
(N10:16)
Datalink A1
M1:1.3
(N10:3)
M1:1.17
(N10:17)
Datalink A2
M1:1.4
(N10:4)
M1:1.18
(N10:18)
Datalink B1
M1:1.5
(N10:5)
M1:1.19
(N10:19)
Datalink B2
M1:1.6
(N10:6)
M1:1.20
(N10:20)
Datalink C1
M1:1.7
(N10:7)
M1:1.21
(N10:21)
Datalink C2
M1:1.8
(N10:8)
M1:1.22
(N10:22)
Datalink D1
M1:1.9
(N10:9)
M1:1.23
(N10:23)
Datalink D2
M1:1.10
(N10:10)
M1:1.24
(N10:24)
Parameter Protocol Word #1
M1:1.11
(N10:11)
M1:1.25
(N10:25)
Parameter Protocol Word #2
M1:1.12
(N10:12)
M1:1.26
(N10:26)
Parameter Protocol Word #3
M1:1.13
(N10:13)
M1:1.27
(N10:27)
Parameter Protocol Word #4
0004
SWP
Swap
Source
#N10:0
Length
28
SWP
Station 1
Logic Status
Execute LAD 3 - Station 1 Drive Logic
0005
JSR
Jump To Subroutine
SBR File Number
U:3
JSR