Rockwell Automation 1761-NET-DNI DeviceNet Interface (DNI) - Manual (Page 71)

Publication 1761-UM005B-EN-P - October 2006
Application Examples 71
Example Ladder Logic The ladder program example is used to monitor the integrity of the
communications link with the DNI. If something happens and
communications are lost (cable is cut or removed, DNI loses power or
faults) this logic detects that condition. The user can program the
controller to respond to a loss of communications, if desired.
The example ladder logic shown below is available for download
from http://www.ab.com/micrologix. The sample is compatible with
RSLogix 500 programming software. The file name is DNI I-O.RSS and
contains two programs.
• DNI MicroLogix Heartbeat Logic, DNI I-O.RSS Ladder 2 - Main
Program
Monitors the communications link for integrity. This is
considered to be part of the Heartbeat logic associated with the
DNI.
• DNI - COS (change of state) I/O Messaging, DNI I-O.RSS Ladder
6 - COS ML DNI
Moves the Input and Output data inside the controller, for
correct operation with the DNI.
16 18 DF1 Baud Rate 0…5:
0: 38,400
1: 19,200
2: 9600
3: 4800
4: 2400
5: 1200
Series A: 2 = 9600
Series B: 1 = 19,200
0 = 38,400
1 19 DeviceNet Autobaud Disabled (0) or Enabled (1) Enabled (1) Enabled (1)
17 Not
Applicable DNI Mode Standby (0) or
Operational (1)
Operational (1) Operational (1)
Parameter Number Description Range Default Value For this Example,
ENTER
Series A Series B