Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

I2S Configuration (Sample Rate, etc.) -> Second ESP as Bluetooth TX #273

Open
JocB1 opened this issue Aug 23, 2022 · 3 comments
Open

I2S Configuration (Sample Rate, etc.) -> Second ESP as Bluetooth TX #273

JocB1 opened this issue Aug 23, 2022 · 3 comments

Comments

@JocB1
Copy link

JocB1 commented Aug 23, 2022

Hi,

I usw I2S output a.o. with MAX98xxx I2S amplifier. That works fine. The MAX supports 8...96 kHz.

Now I need a way to stream the output from Karadio32 to a Bluetooth Speaker. I found a Projekt with ESP32:

https://github.com/pschatzmann/ESP32-A2DP
https://github.com/pschatzmann/arduino-audio-tools

Connecting Karadio I2S to the second ESP32 (I2S to Bluetooth Transmitter) unfortunately does not work for me yet.

In base-i2s-a2dp.ino the I2S input settings has to be configured.

I tryed this and played a bit araound:

auto cfg = i2s.defaultConfig(RX_MODE);
cfg.i2s_format = I2S_STD_FORMAT; // or try with I2S_LSB_FORMAT
cfg.bits_per_sample = 16;
cfg.channels = 2;
cfg.sample_rate = 44100;
cfg.is_master = false; // master, no microphone
i2s.begin(cfg);

My guess is that something is not set correctly here. Therefore the question which settings Karadio32 actually uses as I2S output format. From the code I have not really figured out.

Would be great if you could get this running, this is certainly a useful thing for other users, too.

Jochen

@JocB1
Copy link
Author

JocB1 commented Aug 27, 2022

I have measured that in at I2S 48kHz is sent. Is there a possibility to change the I2S speed to 44.1 kHz?

@karawin
Copy link
Owner

karawin commented Sep 4, 2022

cfg.sample_rate = 48000;

No?

@JocB1
Copy link
Author

JocB1 commented Sep 10, 2022

Yes,
on the Bluetooth ESP32 this would be the solution, but only for the I2S side. The problem is that A2DP transmits at 44.1 kHz and the sample rate must be the same throughout the chain (according to the author of the BT ESP32 - see also the discussion at Phil's Github). This means that Karadio32 should output the I2S data with 44.1 kHz, so that the Bluetooth ESP can read them with 44.1 kHz and pass them directly to A2DP.

Is it possible to create an additional configuration option for Karadio32 to output 44.1 kHz?

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

No branches or pull requests

2 participants