Allen-Bradley PLC-5 User Manual page 129

For this Field
Scan rack address
Starting group number
Chassis size
Backplane addressing
Range
Keep the following limitations in mind when creating/modifying your scan
list:
A scan list only can have 16 entries because only 16 adapters can be on
channel 2.
The automatic configuration always displays the actual hardware
configuration, except for chassis that have their global inhibit bit set. In
this case, that global bit overrides the automatic configuration. You
must first clear the global inhibit bits for all chassis on the channel, and
then use the autoconfigure function.
Clear global inhibit bits by using the controller status status screen.
A scan list can have a maximum of 16 chassis. Entries cannot be
repeated on the scan list.
Communicating with Extended-Local I/O
A Scan List Contains
1-17 octal (PLC-5/40L controllers)
1-27 octal (PLC-5/60L controllers)
0, 2, 4, or 6
4-slot, 8-slot, 12-slot, 16-slot
1-slot, 2-slot, or 1/2-slot
Automatically calculated based upon rack
address, starting module group and chassis size.
An asterisk (*) after a range indicates the last
valid rack entry.
Publication 1785-UM012D-EN-P - July 2005
8-11