Rockwell Automation 1747-ASB Remote I/O Adapter - Manual (Page 96)

Publication 1747-UM006B-EN-P - June 2003
6-10 Start-Up and Operation
Any discrete I/O module or discretely mapped specialty I/O module
which is mapped into the 1747-ASB module image having only output
image, is scanned by the 1747-ASB module unless:
•
The 1747-ASB module is not receiving communications from the
scanner.
•
The 1747-ASB module is receiving reset, adapter decide
commands and the discrete outputs are being held in their last
state.
Any block transfer mapped specialty I/O module which is mapped
into the 1747-ASB image having only output image, is scanned by the
1747-ASB module only when a block transfer write to the I/O module
occurs.
I/O Module Removal from an Unscanned Slot
When an I/O module is removed from a slot not being scanned by the
1747-ASB module, a 1747-ASB error does not occur and all discrete
outputs under its control are not affected.
Any I/O module not mapped into the 1747-ASB module image is
never scanned by the 1747-ASB module.
Any block transfer mapped specialty I/O module which is mapped
into the 1747-ASB image having only output image, is scanned by the
1747-ASB module only when a block transfer write occurs.