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How to generate customized square wave signal?

I want to use pulse waves of different periods to test the issue of vibration and noise of a stepping motor, so I designed the pulse wave as shown below.

Originally, the pulse wave was generated by the statechart method, but the accuracy seems to be too low and once the timestep is adjusted to 1 microsecond, GIOP cannot send the signal normally.

Is there any way to accurately generate a customized pulse?

Thank you very much

Diagram1 d.vsm

Diagram1.vsm

pulse.xlsx

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Altair Embed

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v2021.1

Accepted answers

Ric_22025

Hi Robert, there is a better solution for what you are trying to do using the PWM block in Embed. You can create much higher frequency switch points using this block than using a state chart. I'm attaching a ppt explaining how to set up the PWM for this purpose and an Embed model that you can use to experiment with. Ric

pwm chirp example.vsm

PWM with variable period.pptx

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Ric_22025

Hi Robert,

This micro has a clock speed of 80 or 90MHz, your model requires hundreds of clock cycles to execute one iteration. On the F28069M running at 90 MHz, I was only able to run the model up to 130 KHz, at this sample rate the %CPU usage was > 91%. Here's a snapshot of it running at that rate.

To achieve the 1MHz speed you are going to have to simplify the PPPWM model significantly and use the %CPU utilization to confirm the micro is actually able to complete an iteration.

Ric

Ric_22025

pwm chirp example.vsm

PWM with variable period.pptx