Author Topic: How to find program scan time.  (Read 10660 times)

Ken Talley

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How to find program scan time.
« on: October 29, 2002, 06:03:36 PM »
Hello,

Yep I am beggin' for another freebee, only because I know someone can probably tell me how to do it a lot faster than I can figure it out myself.  Yes, I am being lazy.
What is the easiest way to find the actual scan time of a program on a t100md+?  A value generated in one of the DM's or 32 bit integer would work, as I could check it with online monitoring.  I am sure this is relatively simple but have not had to work with highspeed counters yet.

As always, your responses are greatly appreciated.

By the way, no ideas on the lock up problem or was my question too general?

Thanks,

Ken
« Last Edit: December 31, 1969, 04:00:00 PM by 1076562000 »
Ken

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Re: How to find program scan time.
« Reply #1 on: October 29, 2002, 07:24:21 PM »
To measure the actual scan time, use an output and connect it as follow:
| ? ? ? ?Out1 ? ? ? ? ? ? ? ? OUT1
|----|/|---------------(OUT)

Then hook up an oscilloscope and observe the square wave generated by the output "OUT1". The scan time is half of the period.

The scan time measured is just the average scan time of the ladder logic, it doesn't measure execution time of a Custom function if it is a differentiated version. If you want to measure the scan time of a Custom function, then convert it temporarily into a non-differentiated version and measure the increase in scan time due to the execution of this custom function.
« Last Edit: December 31, 1969, 04:00:10 PM by -1 »
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