Rockwell Automation 1747-SDN SLC 500 DeviceNet Scanner Module User Manual - Manual (Page 119)

Publication 1747-UM655B-EN-P - June 2007
Data Map Example 119
The processor writes output data for each scanned device in the
scanner's discrete-output data table. The scanner then maps each bit
into a strobe message that is sent to all scanned devices. The bit
number, where a particular device's data is mapped, directly
corresponds to that device's MAC ID. This is true for mapping into the
scanner's data table as well as the scanner's strobe message. For
example, node # 11's output bit is mapped in bit number 11 of the
scanner's output data table. In addition, this same output bit is
mapped from bit 11 of the data table to bit number 11 in the strobe
message.
In this example, nothing is mapped from the DeviceNet output
data area of the processor's M0 file. All output data is mapped
from the processor's output image table to the scanner's
discrete-input data table.
1747-SDN Output Strobe Message
The strobe message contains one bit for
each scanned device on the network.
1747-SDN Module Discrete
Output Data Table
15
31
47
63
11 0
16
32
48
Word 1
Word 2
Word 3
Word 4
15 0 Word 0
Word 0 Command (1 Word)
Words 1…31 Device Output Data (31 Words)
Words 0…223 DeviceNet Output Data (224 Words)
Words 224…255 Client Server Table (32 Words)
SLC Processor M0 File
SLC Processor Output Image Table
Bit Number
63 - - - - - - - - - - - - - - - - - - - - - - - -- - - - - - - - - - - - - - 0 11