Hardware reference guide

Network Configurations
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As a deterministic token-passing network, Modbus Plus communicates at one
megabaud for fast access to process data. It’s strength is its ability to control real-
time control devices like I/O and drives, without degraded performance due to
loading or traffic.
Bridging between Modbus and Modbus Plus is done automatically on CPUs and
Modbus Plus network modules.
The bridge mode redirects Modbus messages onto the Modbus Plus network for
easy connectivity between Modbus and Modbus Plus devices.
A summary of the available services on Quantum Modbus and Modbus Plus ports
is given in the following table.
Modbus and Modbus Plus Services
The following table shows the Quantum Modbus and Modbus Plus services.
Type Service Description Native CPU Ports NOM 1-2 Ports NOM 3-6 Ports
Modbus Modbus
Plus
Modbus Modbus
Plus
Modbus Modbus
Plus
Modbus
Services
Default Modbus Port Parameters Y - Y - Y -
Configurable Modbus Port
Parameters
Y- Y - -
Modbus to Modbus Plus Bridging - - -
Local CPU Programming - - N -
Remote CPU Programming over
Modbus Plus
---
Modbus access to local CPU Y - Y - N -
Modbus access to remote CPU
over Modbus Plus
Y- Y - Y-
Modbus Network Slave Support Y - N - N -
Modbus Master support with
XMIT Loadable
Y- N- N-
Executive Firmware Loading
Support
Y- N- N-