Rockwell Automation 1747-ACNR15 ControlNet Adapter Module User Manual - Manual (Page 45)

Publication 1747-UM003A-EN-P
Application Examples 4-17
The Status Address field must also be filled in. This field supplies Connection
Status information to the processor for each unique connection. The starting
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. 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 pair, M1:3.600/00.
NOTE
There is a 2-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-ACN15 chassis is
written to I:3.3 in the SLC processor’s input image.
The starting input address configured in RSNetWorx for
this rack connection was I:3.1, but I:3.1 and I:3.2 are used
for rack slot status information. Therefore, the actual input
data begins after the 2 words of status information. I:3.4 is
not used in this example because although 32 input bits are
assigned to slot 1, the 1746-IA16 only uses the first 16
input bits.
I:3.5 and I:3.6 are 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:3.3 is the
output image word written to the output module located in
slot 2 of the 1747-ACN15 chassis.