Rockwell Automation 1747-SDN SLC 500 DeviceNet Scanner Module User Manual - Manual (Page 136)

Publication 1747-UM655B-EN-P - June 2007
136 Data Organization
SLC M1 File
The SLC M1 file is a file with up to 256 words or more that can be
used to transfer a large quantity of information to the module with a
single SLC instruction.
The first 150 words are used for data transfer from the module. The
remaining 106 words are reserved for:
•
device active table.
•
node status.
•
scan counter.
•
device idle table.
•
device failure table.
•
auto verify table.
•
explicit message program control.
For a details on the mapping of input and output image tables, refer to
page 133.
Device Active Table
Words 206…209 in the M1 file are used for the Device Active Table.
The scanner assigns one bit in consecutive order to consecutive
device addresses starting at node 0 at M1.S.206/0. If a bit is set, it
indicates that the node is in the scanner’s scanlist and has successfully
communicated with the module. The bit is reset if the scanner tries to
communicate to the node but the node has gone offline.
Node Address/Status Indicator
Word 210 is used for node address and scanner diagnostic information
displayed in numeric codes. The high byte is the node address and
the low byte is the status for that node. These codes and their
descriptions are listed on page 91.
IMPORTANT
Transferring data using this file takes more time than using the
input image table.