The Industrial Raspberry Pi Forum

Posted: **07 Dec 2022, 09:42**

Hello,

The following Python script (IP-address is replaced by x's) gives continually repeated warnings resulting from line 5 (

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pass

):

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revpimodio2\helper.py:614: RuntimeWarning: cycle time of 50 ms exceeded - can not hold cycle time!

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import revpimodio2
revpi_ip = "xxx.xxx.xxx.xxx"
rpi = revpimodio2.RevPiNetIO(revpi_ip, autorefresh=True)
while True:
    pass

This occurs due to

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ProcimgWriter

instantiated by

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RevPiNetIO

through

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modio

, which cyclicly reads the IO values from the Revolution Pi.
Simply writing (or reading) an IO instead of performing some task in a while loop works just fine. Most likely because the program is able to finish within the first cycle.
However,

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ProcimgWriter

should be run in a separate thread as I understand. That would mean that the while loop in the above script should not interfere and should not be the cause of any

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RuntimeWarnings

.

Why is this happening and how do I solve it?

Kind regards, any help is appreciated!

Posted: **07 Dec 2022, 09:56**

Hi RiSpa!

Yes, the ProcimgWriter is a Thread, inside of your python process. Your code:

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while True:
    pass

is using all resources of our process and the ProcimgWriter thread can not hold the cycle time.

The Industrial Raspberry Pi Forum

Cycle time exceeded without using cycleloop() or mainloop()

Cycle time exceeded without using cycleloop() or mainloop()

Re: Cycle time exceeded without using cycleloop() or mainloop()