ICP DAS USA DB25 - Manual (Page 13)

DeviceNet to PLCs or Devices
7
D
EVICE
N
ET TO
PLC
S OR
D
EVICES
The ”DeviceNet to Motor Drives” application allows a DeviceNet Host device to access data registers in
up to 32 serial PLCs or Devices via Explicit Messages and/or I/O Data.
Explicit Messages allows the DeviceNet Host to issue requests to the DN-3000 to read or write specific
PLC/Device data registers. The DN-3000 converts those requests into serial communications requests in
the selected serial PLC’s or Device’s protocol.
I/O Data allows the DN-3000 to exchange a fixed set of PLC/Device data registers between a DeviceNet
Host and serial PLCs or Devices. The DN-3000 writes Output Data received from the DeviceNet Host to
fixed PLC/Device data registers (see Output Data Table in this section) in the connected serial PLCs or
Devices. Input Data is read from fixed PLC/Device data registers in the connected serial PLCs or
Devices and sent to the DeviceNet Host (see Input Data Table in this section).
Important Note: The DN-3000 can be used to access only data registers in the selected PLCs or
Devices. See the Application Notes for the selected PLC/Device for more information.
D
EVICE
P
ROFILE
The DN-3000 is based on the “PLC/Device Gateway” Device Profile, a vendor-specific extension of the
“Communications Adapter” Device Profile (described in the “ODVA DeviceNet Specifications”). This
Device Profile introduces two new vendor-specific Objects: the “PLC/Device Interface Object” and the
“PLC/Device Command Object”. Documentation on this profile and these objects are available from
Panel-Tec, Inc.
The DN-3000 is a Group 2 Only Server utilizing the Predifined Master/Slave Connection Set (as
described in the (ODVA DeviceNet Specifications”). It supports both Explicit Messaging and Polled,
Change-of-State (COS) and Cyclic I/O connections to a DeviceNet Host. It does not support Bit-Strobed
I/O connections.
To access register data via Explicit Messaging, the DeviceNet Host must issue an explicit Get_Member or
Set_Member request to the desired “PLC/Device Interface Object” Instance (based on PLC/Device
Address) of the DN-3000.
If Polled, COS and/or Cyclic I/O connections are to be used, you must first set up the I/O
configuration of the DN-3000 with the DN3000 Configuration Editor software. See I/O Data
Configuration in this section.