Rockwell Automation 1203 Serial Communications Module Series B - Manual (Page 23)

2–9 Installation
1203–5.5 September 1995
Use SW3–4 to enable and disable Datalink C messaging:
SW3 Function
O
–
8 7 6 5 4 3 2 1
Disable Datalink C messaging.
O
–
8 7 6 5 4 3 2 1
Enable Datalink C messaging.
Use SW3–5 to enable and disable Datalink D messaging:
SW3 Function
O
–
8 7 6 5 4 3 2 1
Disable Datalink D messaging.
O
–
8 7 6 5 4 3 2 1
Enable Datalink D messaging.
Use SW3–6 to enable and disable duplicate message detection:
SW3 Duplicate Message Detection
O
–
8 7 6 5 4 3 2 1
Disable duplicate message detection.
O
–
8 7 6 5 4 3 2 1
Enable duplicate message detection.
Use SW3–7 and SW3–8 to set the default application timeout value.
The default value is used for application timeout unless the user
writes a value to the application timeout address in the Serial
Communications Module data table. This address is N42:3. If
power is removed, the default value is reloaded during power–up.
SW3 Application Timeout Default Value
O
–
8 7 6 5 4 3 2 1
No timeout (disabled)
O
–
8 7 6 5 4 3 2 1
1 second
O
–
8 7 6 5 4 3 2 1
30 seconds
O
–
8 7 6 5 4 3 2 1
60 seconds
In DH–485 mode, the application timeout function is as follows:
•
If the application timeout is set to zero, the module will not cause
the SCANport device to fault if DH–485 communications are
disrupted.
•
If the application timeout is set to a non–zero value, the module
causes the SCANport device to fault if a DH–485 device that had
sent a message to data table N41 drops off the network.