Rockwell Automation 1747-SCNR ControlNet Scanner Module Reference Manual - Manual (Page 92)

Publication 1747-RM623D-EN-P - June 2006
E-14 Application Examples
Words I:3.0 and O:3.0 are reserved. Note that the input data
from the 1746-IA16 is found in the processor’s input image word
I:3.3, the output data written to the 1746-OB16 module will be
from the processor’s output image word O:3.2.
You must also enter a value in the Status Address field. This field
supplies Connection Status information to the processor for each
unique connection. The bit address for this field must be an
even number, because two consecutive bits are used as status
for each connection. The even numbered bit indicates whether
the connection is open or closed and the odd numbered bit
indicates whether the connection is in normal operation or Idle
mode. In this example, the starting address chosen is the first
available bit, M1:3.600/00.
You have successfully configured a rack connection to the remote
chassis to communicate with the two discrete I/O modules. At this
point, you may also configure the state of the outputs in the remote
ControlNet Chassis when the processor is placed into the Program
Mode or if communications is lost to the remote chassis. This is
optional. The default is to turn all outputs off when one of the two
conditions occur. To select other options:
a. Click the Advanced tab in the Connection Properties window.
IMPORTANT
There is a two-word offset for input data for rack
connections. Therefore, for this example, the input data
for the input module in slot 1 of the remote 1747-ACNR15
chassis will be written to I:3.3 in the SLC processor’s input
image.
The starting input address configured in RSNetWorx for
ControlNet software for this rack connection was I:3.1, but
I:3.1 and I:3.2 are used for status information. Therefore,
the actual input data begins after the two words of status
information. I:3.4 is not used in this example because an
output module resides in slot 2.
Also, note that there is no offset for the outputs in a rack
connection. O:3.2 is the output image word written to the
output module located in slot 2 or the 1747-ACNR15
chassis. In addition, no offset applies to module
connections at all. For this example, the input and output
data for the 1746-NIO4V module is located in M1:3.3,
M1:3.4, M0:3.3, and MO:3.4. M1:3.3 and MO:3.3 are the
starting addresses entered in RSNetWorx for ControlNet
software for the module connection.