Help with understanding the frequency output from the volume in imx6ul on varicsite som board

[Asaf3425423]

Hello, we want to look with scope on the analog output of the voice from the imx6ul (pins number 12 and 16- HPROUT and HPLOUT from the varicsite som board). We want to set the output to transmit the data in 1kHz. Is there a way to do it? What is the frequency now? Is it possible to change it to transmit in sinusoidal wave that can make us measure it simpler?

[Manuel_Salas]

Hello @Asaf3425423 

if you're not playing any audio, the output is idle. 

You can try something like :

$ aplay -D default sine_1kHz.wav

NOTE: You should have a sine_1kHz.wav.

Also, you can make a Python script to generate 1kH:

import numpy as np
import sounddevice as sd

fs = 44100
f = 1000
duration = 5

t = np.linspace(0, duration, int(fs*duration), endpoint=False)
wave = 0.5 * np.sin(2 * np.pi * f * t)

sd.play(wave, samplerate=fs)
sd.wait()

NOTE: You must sure that you have installed numpy, sounddevice on python and libportaudio2 libportaudiocpp0 portaudio19-dev in your Yocto image.

Then, reproducing the audio you’ll see a clean sine wave.

I hope this information can helps to you.

Best regards,

Salas.