Bluetooth and SD Card

[13Pixel]

Hello, I want to create a project with ESP32 and create something like bluetooth speaker that could play audio from smartphone and SD card. Could I achieve this using this library?

[pschatzmann]

Sure, to implement a bluetooth speaker, just look at the A2DP sink examples

Don't forget to read the documentation that can be found in the Readme and Wiki!

[13Pixel]

Thank you

[GaiVana]

Hello. I'm trying to do an ESP32 project that takes sound from a Blluetooth or SD card and sends it via I2S to a DSP. When bluetooth is stopped the source is SD card, when SD card is stopped the sound is from bluetooth. Control with buttons. Everything works fine with your library. But I need additional control of indicator and DSP. When I put these additional functions in the main loop, the sound from the SD card cracks. I tried splitting the tasks on different CPU cores. So that the SD card (audio.loop();) works on Core 0, and the additional functions on Core 1. But in this case only SD works. Control functions from another cycle do not work. Is there a possible solution to this problem? I am using Arduino IDE, ESP32-WROOM

[pschatzmann]

There are quite a few solution approaches to your problem

• try to keep the delay caused by your additional functions as small as possible!
• try to increase the i2s buffer size/count so that I2S is not running out of data during these delay
• Split up the processing into different tasks and make sure that each task is getting a chance to do some work by calling delay() or if all tasks have the same priority a yield() will do.

By the way you can find this in the documentation!

[GaiVana]

Thank you. This solved the problem for me.
To switch the sound from SD card to Bluetooth or vice versa, I use ESP.restart(); and reconfigure similar to the one shown in https://github.com/pschatzmann/arduino-audio-tools/blob/main/examples/examples-audiokit/player-sd_a2dp-audiokit/player-sd_a2dp-audiokit.ino.
Maybe there is another way of switching, without restarting the controller?

[pschatzmann]

It depends: if you want to release the full memory and be able to start A2DP again this is the only way.
Just look at the documentation of the end() method in the documentation