GPIO extension not working

I have had my project with matrix voice to control the Servo motor.
but trying to connect the servo cables on the GPIO Extension there is no signal reaching there.

Any solution to that will be appreciated.

Hi @Cknick,

Welcome to the community!

Can you show us the snippet of your code with the servo control and let us know what pins you connected the servo motor to? Sometimes the min_pulse_ms parameter needs to be adjusted through trial and error according to the servo PWM characteristics. Maybe try some values between 0.2 to 0.8.

Depending on the make & model of your servo, please also ensure you have the appropriate voltage input to power it.


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Sorry I took time to reply.

I tried to replicate the demo Episode 107 on the control of the servo. Well, I was able to obtain the angles but when I used the oscilloscope to detect the pulses on pin 4 (extension GPIO of Matrix Voice, V1.0 / 2018) I got no signals. Please help me on this front. Thank you


I assume you have ensured that you have the correct voltage powering the servo as per its specification.

A good test at this point would be to change the servo output pin in the code to be a different GPIO and then switch the servo to that GPIO to see if it works.

If the issue still persists, I recommend testing with the Raspberry Pi’s gpio utility using wiringPi, see CLI commands here, so you can set pins in the CLI and measure the voltage to ensure that they are working.

Let me know how it goes from here and we can troubleshoot further, if necessary!