Specifications

STB NIP 2311 Services
124
EIO0000000051 6/2010
The Input Data and I/O Status Process Image
Input data and I/O status information from the I/O modules are sent to the input
process image area. The fieldbus master or another monitoring device (for example,
an HMI panel (see page 243)) can view data in the input data image area.
All eight I/O modules are represented in the input process image area. Their
assigned registers start at 45392 and continue in the order of their island bus
addresses.
A digital I/O module uses two contiguous registers:
z Digital input modules use one register to report data and the next to report status.
z Digital output modules use one register to report echo output data and the next
to report status.
NOTE: The value in an echo output data register is basically a copy of the value
written to the corresponding register in the output data process image area
(see page 122). Generally, the fieldbus master writes this value to the NIM, and the
echo is of not much interest. If an output channel is configured to perform a reflex
action (see page 230), however, the echo register provides a location where the
fieldbus master can view the current value of the output.
The analog input module uses four contiguous registers:
z The first register reports the data for channel 1.
z The second register reports the status for channel 1.
z The third register reports the data for channel 2.
z The fourth register reports the status for channel 2.
The analog output module uses two contiguous registers:
z The first register reports the status for channel 1.
z The second register reports the status for channel 2.