Rockwell Automation 20-750-ENETR PowerFlexDual-Port EtherNet/IP Option Module - Manual (Page 100)

100 Rockwell Automation Publication 750COM-UM008A-EN-P - July 2012
Chapter 6 Using Explicit Messaging (Adapter mode only)
Table 5 - Explicit Messaging Class Code Compatibility with PowerFlex 750-Series Drive
Performing Explicit
Messaging There are five basic events in the Explicit Messaging process. The details of each
step will vary depending on the type of controller being used. See the
documentation for your controller.
Figure 23 - Explicit Message Process
TIP To message to another device in a different drive port, see the Instance table in
Appendix C:
• DPI Parameter Object section on page 163 for Device parameters.
• Host DPI Parameter Object section on page 177 for Host parameters.
In the Message Configuration dialog box, set the Instance field to an appropriate
value within the range listed for the port in which the device resides.
IMPORTANT PowerFlex 750-Series drives have explicit messaging limitations. Table 5 shows
the EtherNet/IP Object Class code compatibilities for these drives.
EtherNet/IP Object Class Code Compatibility Explicit Messaging Function
Parameter Object 0x0F No Single parameter reads/writes
DPI Parameter Object 0x93 Yes (1) with limitations
(1) Enables access to drive parameters (Port 0), DPI device parameters (Ports 1…6 only), and Host parameters (Ports 7…14 only). For
example, DPI Parameter Object Class code 0x93 can access a Safe Speed Monitor option module in Port 6. However, Class code 0x93
cannot access, for example, the Host parameters in a 24V I/O option module in Port 5. See
DPI Parameter Object on page 163 for
instance (parameter) numbering.
Single and scattered parameter reads/writes
Host DPI Parameter Object 0x9F Yes (2) with limitations
(2) Enables access to drive parameters (Port 0) and Host parameters for all ports (1…14). Host DPI Parameter Object Class code 0x9F
cannot access DPI (device) parameters. For example, if a 20-750-DNET option module is in Port 4, its Host parameters can be
accessed, but not its DPI (device) parameters. See
Host DPI Parameter Object on page 177 for instance (parameter) numbering.
Single and scattered parameter reads/writes
IMPORTANT There must be a request message and a response message for all Explicit
Messages, whether you are reading or writing data.
Event Description
➊ You format the required data and set up the ladder logic program to send an Explicit Message request to the
scanner or bridge module (download).
➋ The scanner or bridge module transmits the Explicit Message Request to the slave device over the network.
➌ The slave device transmits the Explicit Message Response back to the scanner. The data is stored in the
scanner buffer.
➎
➊
➋
➌
➍
Complete Explicit
Message
Retrieve Explicit
Message Response
Set up and send Explicit
Message Request
Network Network