Rockwell Automation 1336-GM1 Remote I/O Communications Module - Manual (Page 24)

2–8 Configuring the Module
Setting Datalinks
SW 3.7 through SW 3.4 enable or disable datalinks. A datalink is a
type of pointer used by some SCANport products to transfer data to
and from a controller. You can use datalinks to change or monitor the
value of parameters without using block transfer messages. Each
datalink consists of two 16-bit words of input and two 16-bit words of
output. You can enable up to four datalinks (eight words in and out).
Refer to Chapter 4 for detailed datalink information and examples.
Figure 2.6 Datalink Switches
Important: Ensure that datalinks are supported and enabled in the
SCANport product before you enable them in the Remote
I/O module. You do not have to use datalinks. If you do
use them, remember that a datalink in a drive can be used
by only one communications module. Datalinks do not
write to the EEPROM.
To edit the datalinks, you need to:
1. Refer to the following table to determine the settings for SW 3.7
through SW 3.4:
2. Slide the switches to their appropriate positions.
3. For each enabled datalink, record “Datalink [A, B, C, or D]” in
the first two available module groups (words) of the output and
input columns of your I/O image table on page 2–4.
Settings take effect when a module or board first receives power.
When you change a setting, you must remove and then reapply power
for the new setting to take effect.
Setting the Truncate Last Datalink Feature
SW 3.8 enables or disables the truncate last datalink feature. All
datalinks are two words. If this feature is enabled, the second word of
the last datalink is deleted. For example, if datalinks A and B are
enabled and this feature is enabled, Data In B2 and Data Out B2 are
truncated. This feature can save rack space by maintaining an even
number of words in your rack.
Important: This feature is available only on modules with firmware
1.02 or later.
Function
Datalink D
SW 3.7 Datalink C
SW 3.6 Datalink B
SW 3.5 Datalink A
SW 3.4
Disable 0 0 0 0
Enable 1 1 1 1
Off = 0
On = 1
Use SW 3.7 through SW 3.4 for
setting the datalinks.