Rockwell Automation 1747-SN Remote I/O Scanner - Manual (Page 46)

Publication 1747-UM013B-EN-P - January 2005
4-2 Scanner Configuration and Programming
The illustration below shows how logical racks, logical groups, and
words are allocated within the I/O image files. Note that this
illustration describes the input image file. The scanner’s output image
file is the same, except that its addressing scheme starts with O:e.0
and ends with 0:e.31.
0 7 8 15
0 7 17 10 Bit Number Octal
Logical
Rack 1
Logical
Rack 0
Logical
Rack 2
Logical
Rack 3
Input Image
Output Image
SN Series B Scanner
(RIO Master)
Scanner Input and Output Images
The scanner
accommodates
up to 32 words
of output for
remote devices.
The scanner
accommodates
up to 32 words
of input from
remote devices.
Word 10
Word 1 1
Word 8
Word 9
Word 14
Word 12
Word 13
Word 15
Logical
Rack 1
Word 7
Word 5
Word 6
Word 3
Word 4
Word 1
Word 2
Word 0
Logical
Rack 0
Logical
Rack 2
Word 26
Word 27
Word 24
Word 25
Word 30
Word 28
Word 29
Word 31
Word 23
Word 21
Word 22
Word 19
Word 20
Word 17
Word 18
Word 16
Logical
Rack 3
Bit Number Decimal
0 7 8 15
0 7 17 10 Bit Number Octal
Bit Number Decimal
Word 10
Word 1 1
Word 8
Word 9
Word 14
Word 12
Word 13
Word 15
Word 7
Word 5
Word 6
Word 3
Word 4
Word 1
Word 2
Word 0
Word 26
Word 27
Word 24
Word 25
Word 30
Word 28
Word 29
Word 31
Word 23
Word 21
Word 22
Word 19
Word 20
Word 17
Word 18
Word 16
Note that some RIO devices (e.g.,
1771) use octal bit numbers.