Rockwell Automation PLC-5 Fieldbus Solutions for Integrated Architecture User Manual - Manual (Page 169)

Publication 1757-UM006A-EN-P - May 2002
Using the 1788-CN2FF, ControlNet-to-FOUNDATION Fieldbus H1 Linking Device 7-9
Discrete Inputs This section describes configuration of the linking device to access
any discrete value (and status) in a Fieldbus device. It also describes
the attributes of the created ControlNet discrete input object.
The linking device contains one MDI block instances on each of the
two channels. Each instance of the MDI block is the software
equivalent of a discrete input module in a I/O subsystem. Each MDI
block has eight channels, with each channel containing a byte and a
status pair. The linking device assigns a tag to each MDI block in the
form CNetMacIdxx_DI_Modulei-j, where xx is the ControlNet network
address, i is the Fieldbus channel number, and j is the module or
instance number.
Configuration of Discrete Inputs
The NI-FBUS Configurator lists all the devices and the function blocks
in each device in its browse window. This includes the DI function
blocks in the Fieldbus devices and the MDI function blocks in the
linking device. You must connect the Fieldbus DI function blocks that
will be accessed by the ControlNet controllers (or devices) to the MDI
channels as shown in Figure 7.6. The remaining configuration is
similar to that for the analog inputs.
Figure 7.6 Sample Single Macrocycle MDI Configuration