Programming instructions

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14.6 GX-Developer Diagnostics
Much of what has been discussed was necessary to troubleshoot programs in
pre GX-Developer days. This information is still useful to display faults to an
HMI, or to save fault codes for future examination, as in the ladder logic above.
Please create a new program and enter the rung shown below:
Take a moment to examine the above logic. What happens when X0 is turned
on? The fixed value 4 is divided by 0 and the result is placed into D0.
This is an illegal operation, since the result is an infinite number. Trigger X0.
To troubleshoot do the following steps:
1. Click on the Diagnostics pull-down menu.
2. Click on PLC Diagnostics. A menu similar to the one below appears: