27 lines
1.2 KiB
Markdown
27 lines
1.2 KiB
Markdown
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**I2S Bluetooth Transmitter**
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Such boards can be connected directly to the I2S output: <br>
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But to do this, `#define SR_48K` must be activated in Audio.h so that the I2S frequency is always 48KHz.
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If you still have an old ESP32 in your box, you can use it to simulate this board. PSRAM is not required.
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The BT transmitter is the slave and is connected in this way, the DAC serves as an analogue output, but is not necessary.
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The ESP32-A2DP library is used by P. Schatzmann, https://github.com/pschatzmann/ESP32-A2DP.git
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As the I2S output of the audioI2S library not always outputs 44.1KHz, it is scaled internally to 44.1KHz for compatibility. 8000Hz, 22050Hz, 44100Hz and 48000Hz are possible.
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This is necessary because the ESP32 BT library expects this sample rate. This means that old BT devices can also be used.
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It doesn't matter what sample rate the audio source has.
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Test circuit: the audioI2S library is running on the left, the BT transmitter on the right
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