Rockwell Automation 1747-ASB Remote I/O Adapter - Manual (Page 60)

Publication 1747-UM006B-EN-P - June 2003
4-6 Configuration
If you want to use complementary I/O, two 1747-ASB modules are
required. One 1747-ASB module is configured as a primary chassis,
the other as a complementary chassis. If a primary chassis exists, it is
scanned first.
The 1747-ASB modules in the primary and complementary chassis
must be configured to have the same:
•
addressing mode, using SW3-5,6
•
logical group number, using SW1-7,8
•
baud rate, using SW2-1,2
•
image size, using SW2-5 through 8
The 1747-ASB modules in the primary and complementary chassis do
not have to be configured to have the same:
•
hold last state selection
•
processor restart lockout selection
•
specialty I/O mode
•
I/O module keying mode
•
link response selection
ATTENTION
!
Because the primary and complementary chassis
images overlap, input and specialty I/O modules
must never share the same image location. Inputs
received by the scanner may be incorrect and RIO
block transfers are not serviced properly.
If an output module shares its output image with
another output module, both output modules receive
the same output information.
ATTENTION
!
If the addressing mode, logical group number, baud
rate, and image size are not the same, unpredictable
operation of both 1747-ASB modules results. No
1747-ASB module errors occur.