Rockwell Automation 1747-BSN Backup Scanner Module User Manual
Page 64
Publication 1747-UM010B-EN-P - September 2003
5-2 Configuration and Programming
The 1747-BSN module’s I/O image structure is described below:
•
The I/O image file consists of four logical racks (numbered 0, 1,
2, and 3) of input image and four logical racks of output image.
•
Each logical rack consists of eight logical groups (numbered 0,
1, 2, 3, 4, 5, 6, and 7).
•
Each logical group consists of two words (an input word and an
output word).
•
Each word consists of two bytes (a high and a low byte). Low
byte is bits 0 through 7 and high byte is bits 8 through 15.
•
Each byte consists of eight bits, with each bit having the ability
to control one discrete I/O point.
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
0
8
1
8
2
8
3
8
4
8
5
8
6
8
7
8
10
8
11
8
12
8
13
8
14
8
15
8
16
8
17
8
Logical
Rack 0
Logical
Rack 1
Logical
Rack 2
Logical
Rack 3
Word 0
Word 1
Word 2
Word 3
Word 4
Word 5
Word 6
Word 7
Word 8
Word 9
Word 10
Word 11
Word 12
Word 13
Word 14
Word 15
Word 16
Word 18
Word 19
Word 20
Word 21
Word 22
Word 23
Word 17
Word 24
Word 26
Word 27
Word 28
Word 29
Word 30
Word 31
Word 25
Rack 0 Group 0
Rack 0 Group 1
Rack 0 Group 2
Rack 0 Group 3
Rack 0 Group 4
Rack 0 Group 5
Rack 0 Group 6
Rack 0 Group 7
Rack 1 Group 0
Rack 1 Group 1
Rack 1 Group 2
Rack 1 Group 3
Rack 1 Group 4
Rack 1 Group 5
Rack 1 Group 6
Rack 1 Group 7
Rack 2 Group 0
Rack 2 Group 2
Rack 2 Group 3
Rack 2 Group 4
Rack 2 Group 5
Rack 2 Group 6
Rack 2 Group 7
Rack 2 Group 1
Rack 3 Group 0
Rack 3 Group 2
Rack 3 Group 3
Rack 3 Group 4
Rack 3 Group 5
Rack 3 Group 6
Rack 3 Group 7
Rack 3 Group 1
I:3.0
I:3.1
I:3.2
I:3.3
I:3.4
I:3.5
I:3.6
I:3.7
I:3.8
I:3.9
I:3.10
I:3.11
I:3.12
I:3.13
I:3.14
I:3.15
I:3.16
I:3.18
I:3.19
I:3.20
I:3.21
I:3.22
I:3.23
I:3.17
I:3.24
I:3.26
I:3.27
I:3.28
I:3.29
I:3.30
I:3.31
I:3.25