Signal update big delay on bus, Trace and Plot inconsistent

[dmeir]

Our setup is as follows:
We have a pump motor controlled over CAN.
I can set the RPM over CAN ("Setpoint_RPM") and it reports back its actual RPM ("ActualPumpRPM").
I'm changing the RPM signal value via an instrument panel button.
The signal is set to be sent on the bus with a cycle time of 50ms. Bus load is low at any given time (<10%).

Now the issue is that every time I change the signal via the button, it takes a significant amount of time (around 600ms) until the device reacts.
To look for the cause I set up both a Trace and Plotter window.

Image shows relation between updated signal and device feedback.

plot.png (19.79 KiB) Viewed 20654 times

Here, the first updated device RPM shows up at timestamp 22.477, 600ms after the setpoint has been changed.

However, if compared to the trace, it becomes clear that the signal doesn't get sent until around 120ms before the first updated device RPM, which would correctly correspond to the device's reaction time.

Image shows the line where the first signal update gets put on the bus.

first_new_data.png (104.85 KiB) Viewed 20654 times

Image shows the line where the first updated response comes from the device.

first_new_feedback.png (106.82 KiB) Viewed 20654 times

Why is the delay between the signal update and the signal being put on the bus so high? How can I reduce this delay?
Why doesn't the plot correctly correspond to the trace?

Additional info:
There's no script running in the background.
When I disable the cycle time, the signal gets sent immediately without delay.
PCAN-Explorer version is 6.7.0.2830

[M.Heidemann]

Hello,


Can you contact us with your Licene-ID?

support[at]peak-system.com