M5StickC or M5StickC PLUS microphone basic example not working [Solved]

miamifish

Hi, I am new to the M5stickc eco system. Wanted to try some experiments with the built-in microphone. Tried to run the example provided with M5Stickc->Basic->Microphone. Compiles and runs. I can see "Mic Test" on tft. But it doesn't do anything past that. Interestingly the M5Stickc->Basic->FactoryTest is the only microphone example that works and shows the wave form on the tft screen. I have tried both M5stickc and M5stickcplus. Can someone please provide any thoughts on what I am doing wrong? Please see video of my test in this attached link.
YouTube Link

ajb2k3

You will be lucky to get a response at the moment due to the Chinese New Year.
@felmue do you have any experience with the Stick C mics and Arduino?
Have you tried comparing the microphone code between the two? it could be that something has changed and the code has not been updated.

felmue

Hello guys

I quickly had a look, but I couldn't spot the reason why the example doesn't work. Sorry.
But since the factory test code works maybe you could try to extract the necessary microphone code from there?

Edit: Just had another look using M5StickCPlus and the fix is quite easy. The gain factor needs to be upped to 30 (from 3) like this:

#define GAIN_FACTOR 30

and if you compile for arduino-esp32 version 2.x.x you also need to add this line:

pin_config.mck_io_num = GPIO_NUM_0;

to the pin config.

Thanks
Felix

miamifish

Thank you Felix & ajb2k3! I tried to run it using the above changes and the example runs so well on M5stickc Plus. Is it possible to print the values using the Arduino IDE's serial plotter? I tried it like this, but it is not a clean wave ....!! There seems to be an offset in the signal? Thank you so much for saving the day!

0_1643402786324_Mic_Plotting.jpg

miamifish

Sorry here is print code -

ajb2k3

@felmue said in M5StickC or M5StickC PLUS microphone basic example not working:

Hello guys

I quickly had a look, but I couldn't spot the reason why the example doesn't work. Sorry.
But since the factory test code works maybe you could try to extract the necessary microphone code from there?

Edit: Just had another look using M5StickCPlus and the fix is quite easy. The gain factor needs to be upped to 30 (from 3) like this:
#define GAIN_FACTOR 30
and if you compile for arduino-esp32 version 2.x.x you also need to add this line:
pin_config.mck_io_num = GPIO_NUM_0;
to the pin config.

Thanks
Felix

Thanks @felmue I thought you may be able to solve this one and give the solutions.

felmue

Hello @miamifish

w/o trying it myself one thing that seems wrong to me is the fact that in every loop about READ_LEN (=512) samples are read from the microphone but at the same time you plot about 1000 samples...

Thanks
Felix

miamifish

This post is deleted!

miamifish

This post is deleted!

miamifish

Thank you to @felmue . The original issue I posted was resolved. We can close this post for basic microphone example works just fine after @felmue's suggestions. I will open a separate thread for the issue with regards to microphone offset in M5stickcPlus.