Rockwell Automation 1747-BSN Backup Scanner Module - Manual (Page 71)

Publication 1747-UM010B-EN-P - September 2003
Configuration and Programming 5-9
Examples of Illegal Configurations
Having a primary device configured at Logical Rack 1, Logical Group
2 (bit 5) would be illegal since this image space is already being used
by a complementary device. Having a complementary device
configured at Logical Rack 10, Logical Group 2 (bit 9) would also be
illegal since this image space is already being used by a primary
device.
Note that the complementary device at Logical Rack 8, Logical Group
2 could be an ASB using 10 words (1-1/4 logical racks) of data, and
thereby cross into RIO Logical Rack 9.
The G file configuration above would provide the primary and
complementary input images to the scanner, which are illustrated on
the following pages. The output images would be the same.
Example Scanner Input Image of the Primary Devices
Below are the primary device addresses and sizes. The following
figure contains complementary device addresses and sizes.
•
Device 1 - starting at Logical Rack 0, Logical Group 2 is a
primary 3/4 logical rack device.
•
Logical Rack 1, Logical Group 0 contains no primary device.
•
Device 2 - starting at Logical Rack 1, Logical Group 6 is a
primary 1/4 logical rack device.
•
Device 3 - starting at Logical Rack 2, Logical Group 0 is a
primary 3/4 logical rack device.
•
Device 4 - starting at Logical Rack 3, Logical Group 2 is a
primary 1/4 logical rack device.
•
Device 5 - starting at Logical Rack 3, Logical Group 6 is a
primary 1/4 logical rack device.