Allen-Bradley 160-DN2, User Manual, Page: 64 / 116

Publication 0160-5.18 - June 2003
6-26 Using 160-DN2 with DeviceNet Scanner
Using Explicit Messaging
(Continued)
Explicit Messages for a PLC-5 or SLC Controller
Transaction blocks in PLC-5 and SLC scanners accommodate both
downloading Explicit Message Requests and uploading Explicit
Message Responses. The scanner module can accommodate one
request or response for each transaction block. Each transaction block
must be formatted as shown in
Figure 6.18 or Figure 6.19 .
Figure 6.18
PLC-5 Explicit Message Format
Figure 6.19
SLC Explicit Message Format
Refer to Page 6-27 and Page 6-28 for a description of the data that is
required in each word.
The following table identifies the number of transaction blocks within
a scanner that are reserved for Explicit Messaging.
Bit 15 0 15 0
Word 0 TXID Command TXID Status
Port Size Port Size
Service Address Service Address
Class Service Response Data
Instance
Attribute
Word 6 - 31 Service Data
Word 32
TXID Command TXID Status
Port Size Port Size
Service Address Service Address
Class Service Response Data
Instance
Attribute
Word 38 -
63 Service Data
Bit 15 0 15 0
Word 0 TXID Command TXID Status
Port Size Port Size
Service Address Service Address
Class Service Response Data
Instance
Attribute
Word 6 - 31 Service Data
Scanner
Number of
Transaction Blocks
Words in Each
Transaction Block
Refer to . . .
1771-SDN 10 32 (two blocks can be moved at once) Figure 6.18
1747-SDN 10 32 Figure 6.19
Request
Response
Request
Response