How to enable microphone Adafruit I2S SPH0645 on LPC54114?

[jan4]

Hello,

I am trying to enable an Adafruit I2S microphone (SPH0645) on my LPC54114 board. I've been trying to use the i2s_interrupt_transfer example and the usb audio device example to try and read input from the microphone but I have not been successful.

When I use an I2S audio breakout board and just plug it in the board (pins 16,18,20 on J1), audio output works, so I assumed that this would similarly work for the microphone (pins 10,12,14) but this does not appear to be the case.

I am not really editing any code, so it's more of a question of how to edit to code rather than fixing it (unless it's broken to begin with).

Any tips?

Thank you very much

N.B. the microphone works, I tested it on Arduino MKRZero.

[jeremyzhou]

Hi Jan Polivka,
Thank you for your interest in NXP Semiconductor products and for the opportunity to serve you.
Before answering your question, I was wondering if you can share the SCH of your own boards and introduce the testing process in details, it can help me to figure it out.
I'm looking forward to your reply.
Have a great day,
TIC

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[jan4]

Good morning,

I am not sure what SCH is but if you mean schematic files for the microphone, this is the best I could find.

My testings process using project i2s_interrupt_transfer is:

1. Connect the LPC54114 board through J7 to the computer
2. Connect UDA1334A I2S Stereo DAC breakout to pins 16 - CLK, 18 - WS, 20 - D on J1.
3. Hear sound from the function StartSoundPlayback()
4. Connect the I2S microphone to pins 10 - D, 12 - WS, 14 - CLK on J1
5. Replace StartSoundPlayback() with StartDigitalLoopback()
6. Can't hear anything
7. I try to reconnect the microphone to pins 10 - D, 12 - WS on J1, 9 - CLK on J2
8. Can't hear anything

I also added PRINTF statements to TxCallback and RxCallback in i2s_interrupt_transfer.c. TxCallback PRINTF executes many times, RxCallback PRINTF never executes.

I hope this helps,

Jan

[jeremyzhou]

Hi Jan Polivka,
Thanks for your reply.
Connect the I2S microphone to pin 9 - CLK on J2, others keep same, please give a try.
Have a great day,
TIC

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[jan4]

Hello,

yea, that's the second configuration I tried, see number 7 in the test procedure.

Kind regards,

Jan

[jeremyzhou]

Hi Jan Polivka,
Thanks for your reply.
Okay, I think I may miss some important information, however, I'm not sure, so I was wondering if you can share the picture of the testing platform.
Have a great day,
TIC

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Note: If this post answers your question, please click the Correct Answer button. Thank you!
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