VS1063a audio input to I2S

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jmcexx
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VS1063a audio input to I2S

Post by jmcexx » Mon 2020-09-28 23:21

Hi, my understanding is the I2S is an output from the VS1063a and is a copy of what is being sent to the DAC.

As part of a test mode, I would like to pass the raw data from the ADC to the I2S output. Is there a "bypass" type mode to pass the audio in to audio out? See attached path I'm asking about.
VS1063A_Audio_to_i2s.jpg
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VS1063A_Audio_to_i2s.jpg (45.78 KiB) Viewed 260 times
Thank you,
Ryan

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Panu
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Re: VS1063a audio input to I2S

Post by Panu » Fri 2020-10-02 7:15

The I2S output is a copy of the DAC output, when enabled. So any recording mode which has monitor output to headphones can be output to the I2S out.

But please note that the VS1053/VS1063 I2S output is 16-bit (16 bits per sample, 32 bits per frame), and only very few I2S DACs that really are strictly I2S compliant can understand the 16-bit data.

Almost all I2S dacs expect 24 bits per sample, 64 bits per frame and they usually will not output any audio from a 16-bit source.

-Panu
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pasi
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Re: VS1063a audio input to I2S

Post by pasi » Wed 2020-10-21 12:45

You can start the encoding mode with the preferred channel(s), samplerate (48kHz), and encoding mode (PCM) to get the ADC monitoring at the DAC output. You don't need to read the encoded data.

Then see from the vs1063a datasheet how to enable the I2S output by performing a few SCI (serial control interface) writes.
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