Download How to Check a M580 ERIO System for Cabling Errors CRC errors

How to Check a M580 ERIO System for Cabling Errors
CRC errors are good indicators of hardware level faults like interference or cabling mistakes. In
distributed IO networks this information is accessible via web interface on ConneXium managed switches
but in an Ethernet Remote IO network these switches are build into the CPU and CRA modules. This
tech note explains how to read this information.
The follow methods are used
1. For the CPU ports there is an Ethernet Diagnostic page
2. For the CRA Modules the Ethernet/IP explicit message GUI is used
Terminology
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CRC (Cyclic Redundancy Check)
FCS (Frame Check Sequence)
Both CRC and FCS are destination checks used to sure data as arrived intact. The number of errors
should very low (less than 10) and never change unless a port is unplugged etc. On faulty network the
error count will be in the 1000s and change every few minutes if not quicker.
M580 CPU Ethernet Diagnostic Page
This method is used to check for errors on the CPU switch ports. The screen shot below shows where
the FCS error are found. ETH1 is the service port while ETH2 & ETH3 are the device network ports.
CRA Modules
Open the Ethernet/IP Explicit Message GUI
Enter the following data into the Explicit Message GUI
1.
2.
3.
4.
5.
Enter the IP address of the CRA module
Enter the class, instance & attitude numbers as shown below.
Set the Name field to Get_Attribute_Single
Send the request to the CRA using the Send to Device button
Convert the reply from hex to decimal if needed
Note: Instance number equals port number.
Below is a screen shot showing where in the Unity help files the class, instance & attitude numbers are
found.