Hardware reference guide

Network Configurations
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Quantum Network Interface Techniques
Overview
Quantum communication and networking modules use a variety of different
techniques to interface to the Quantum controller over the local backplane.
Direct CPU Driver
This technique allows the CPU to control high speed data transfers to and from the
communication and networking modules, maximizing throughput and performance.
This technique is used extensively by the Remote I/O network and Hot Standby
system to ensure highly deterministic synchronization of the CPU and I/O scans.
NOTE: Only one Remote I/O Head Interface is supported for each Quantum CPU.
Option Module Interface
This technique allows the communication and networking modules to control data
transfers to and from the CPU, maximizing the flexibility of the communications
interface.
This technique is used extensively by the Modbus Plus and Ethernet peer-to-peer
network modules. The number of option module interfaces supported by each CPU
model is described in the following table.
CPU Interface Support
The following table shows the summary of Quantum CPU option module interface
support in standalone configurations.
NOTE: Refer to Quantum Modbus and Modbus Plus Communications, page 48 for
details of available services on 140NOM2XX00 Modbus Plus Network modules.
Quantum Controller Model
Number
Available Option Module
Interfaces Supported Per CPU
140CPU53414(A) 6
140CPU53414(B) 6
140CPU43412(A) 6
140CPU42402 6
140CPU21304 2
140CPU11303 2
140CPU11302 2