User Defined Can Unit Features - Omron CJ1W-CORT21 Operation Manual

1 Features and System Configuration
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User Defined CAN Unit Features

The User Defined CAN Unit (CJ1W-CORT21) is a CPU Bus Unit which can be installed on an NJ-series
Controller. The User Defined CAN Unit will interface between the CPU of the NJ-series controller and
the CAN bus. The User Defined CAN Unit is connected to the CPU of the NJ-series through the bus of
the controller. The User Defined CAN Unit is connected to the CAN bus with a 5-pin open style connec-
tor.
 CPU Bus Unit
A total of up to 16 CPU Bus Units can be mounted on the CPU Rack or an Expansion Rack. The
total of 16 must include all User Defined CAN Units and all other CPU Bus Units.
 Unit Control and Status
Up to 25 words of control and status information are exchanged between the User Defined CAN Unit
and the CPU Unit. Control bits allow the User program to switch the CAN communication of the Unit
between enabled and disabled mode. Status words provide status and diagnostics information of
the Unit, the CAN network and the state of messages.
 Message Communications
The User Defined CAN Unit supports message communications exchange with the CPU. Four types
of services are supported:
Configuration
• Configure specific memory locations, number of input messages and number of output messages.
• Set the identifiers and method of sending the output messages.
• Set the identifiers of the input messages
• Set the bit rate of the CAN physical layer
Transmission
• Services to send a specific output message
Error Log
• Services to read and clear the error log
Identification Services
• Services to identify the Unit and its firmware version
 Communications Configuration
Before the User Defined CAN Unit is able to operate in a CAN network, the baud rate and sample
point must be configured either using the selector switches on the front of the Unit, or message com-
munications.
 Troubleshooting Functions
The User Defined CAN Unit is provided with a variety of troubleshooting functions for prompt recov-
ery if errors occur.
• Extensive self-diagnostic function at startup.
• Communication exchange flags indicating if message buffers are ex-changed with the bus-
device(s)
• Status and error flags indicating the status of the Unit and the CAN network
• Error log for recording error history data
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CJ-series User Defined CAN Unit Operation Manual for NJ-series CPU Unit (W517)