Rockwell Automation 1760-DNET Pico DeviceNet Communications Module User Manual User Manual
Page 35

Publication 1760-UM003A-EN-P - September 2005
DeviceNet Functions 4-11
The data transfer on the DeviceNet communication bus is indicated in
the following table. The data flow indicates the telegram for reading
the date and time in the Pico (see Read/Write Date and Time on page
6-2).
The Pico DeviceNet communication module has MAC ID = 3. It must
be noted with the data stream that access is implemented in
fragmented form. More information can be found in the ODVA
specification.
Connection ID = CAN Identifier
Meaning
10
9
8
7
6
5
4
3
2
1
0
1
0
MAC ID
Message ID
Message Group 2
1
0
Source MAC ID
0
0
0
Master’s I/O Bit-Strobe Command
Message
1
0
Source MAC ID
0
0
1
Reserved for Master’s Use - Use is
TBD
1
0
Destination MAC ID
0
1
0
Master’s Change of State or Cyclic
Acknowledge Message
1
0
Source MAC ID
0
1
1
Slave’s Explicit/Unconnected
Response Messages
1
0
Destination MAC ID
1
0
0
Master’s Explicit Request Messages
1
0
Destination MAC ID
1
0
1
Master’s I/O Poll Command/Change
of State/Cyclic Message
1
0
Destination MAC ID
1
1
0
Group 2 Only Unconnected Explicit
Request Messages
1
0
Destination MAC ID
1
1
1
Duplicate MAC ID Check Messages
Description
ID
(Hex)
Length
DeviceNet - Byte (Hex)
0
1
2
3
4
5
6
7
Master sends a request (Hex) with:
41C
8
80
00
32
64
01
93
05
00
DeviceNet Specific:
Byte 2 - Service Code = 32
Byte 3 - CLASS ID = 64
Byte 4 - Instance ID = 01
PicoLINK Specific
Byte 5 - Attribute ID = 93
Byte 6 - Len = 05
Byte 7 - Index = 0
Confirmation of the slave
(Fragmentation protocol)
41B
3
80
C0
00