Allen-Bradley DeviceNet 1756-DNB - Understanding a Scan List Example

B–2 Scan List Example
Publication 1756–6.5.15 – July 1998
This example illustrates how each Scan List Configuration screen
appears when the mapping example’s network is configured.
DeviceNet network
photoelectric sensors
RediSTATION operator interfaces
RediSTATION operator interfaces
Two input bits from each photoelectric
sensor will be mapped. One status bit and
one data bit. The data bit is needed
quickly; therefore, this input data will be
mapped to the communication module’s
discrete input data table.
Two input bits from each RediSTATION
operator interface will be mapped.
One bit for the green start button and
one bit for the red stop button.
One output bit for each operator interface
will also be mapped: one bit for each
operator interface’s indicator
light (on/off).
Series 9000 photoelectric sensor
RediSTATION operator interface
indicator light
green start button
red stop button
1 byte
1 byte
1 byte
input
output
The RediSTATION
operator interface produces
one byte of input data and
consumes one byte of
output data.
status
bit
data
bit
bit for
green button
bit for
red button
bit for
indicator light
Node 1 Node 2
Node 3 Node 4
Node 5 Node 6
Node 7 Node 8
The photoelectric sensor produces
one byte of input data and consumes
one bit of output data.
photoelectric
sensor
photoelectric
sensor
Node 22
FLEX I/Ot rack
1770–KFD
communication
interface module
host platform running Windows NT or
Windows 95 with DeviceNet Manager
software
Node 0
SD
DD
S
1756–DNB in ControlLogix chassis
DEVICENET
Node 62
U
nd
e
r
s
tanding
a
Scan List Example