Mitsubishi Electric MELSEC iQ-RJ71C24-R2 - Chapter 6 Using the Programmable Controller Cpu Monitoring; Overview

6 USING THE PROGRAMMABLE CONTROLLER CPU MONITORING FUNCTION
6.1 Overview
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6 USING THE PROGRAMMABLE CONTROLLER
CPU MONITORING FUNCTION
This chapter explains the programmable controller CPU monitoring function with which the C24 monitors the programmable
controller CPU based on the monitoring information reregistered by the user.
6.1 Overview
This section explains an overview of the programmable controller CPU monitoring function.
Transmitting data without a program
• The programmable controller CPU monitoring function enables C24 to monitor the CPU module on the host station at time
intervals set by the user by reregistering data to be used for the programmable controller CPU monitoring function. Data
transmission to the target device communicating with the MC or nonprocedural protocol is possible without a program.
• The following monitoring information selected by the user can be sent to the target device as the CPU module monitoring
results.
• There are two timings for transmitting the programmable controller CPU monitoring results to the target device; fixed cycle
send and condition match send.
The fixed cycle send transmits the programmable controller CPU monitoring results each time when CPU module is
monitored.
The condition match send transmits when the information read from the CPU module satisfies the defined conditions and
when an error is detected in the CPU module.
Simplifying device monitoring procedure
When device monitoring is performed by communication using the MC protocol, the target device must repeatedly perform
monitor request transmission and monitor data reception processing after it executes monitor registration.
By designating the fixed cycle send for the programmable controller CPU monitoring function, the device data can be
monitored without performing the monitor request reception processing.
Notifying programmable controller CPU error
In the condition match send, error information can be transmitted to the target device whenever CPU module error occurs
without any programming.
Transmiss
ion
method
Monitoring result Without the
modem function
Combined use of
the modem
function (modem
communication)
Data
transmission
Devices on the host station CPU module
(information of the device to be monitored)
Numeric value stored in a word device 
ON/OFF status of a bit device
Status of module of the host station CPU module
Target device
CPU error information Monitoring device information
Abnormal detection
Error
occurred