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I am doing some speech recognition, and my phone is my microphone. I have used it to collect data for PC and would like to do the same on my Tiva C launchpad. I planned on using an app,such as this one, to send data from a phone's microphone to an audio jack, in real time.

I am wondering how to connect the phone and the MCU. With a 3.5mm jack and an aux cable? Stripping the wires and plugging them in ADC input pins? (L or R ?) Is it possible to get the same data on PC and MCU with the same speech signal?

EDIT: I should mention that the sound produced using this app is as good as the recorded one.

SOLVED. Look in the comments.

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    \$\begingroup\$ Have a look here: How to give analog input from 3.5 mm jack to FPGA (Spartan 3e) - you'll need to do pretty much the same. Use the tip and ring of a 3.5mm jack plug (I suspect your phone only has one mic so it will output the same on L and R channels of the jack). \$\endgroup\$ – Finbarr Dec 13 '17 at 16:17
  • \$\begingroup\$ @Finbarr Okay, I now understand why it's not possible the way I thought it's gonna be. Can you recommend me a rectifier circuit then? Or a board 'component' that has a mic + everything else? \$\endgroup\$ – Desperado Dec 13 '17 at 17:04
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    \$\begingroup\$ You don't need the rectifier - that answer was about measuring the peak level. Just follow the circuit diagram shown there and you should be fine. \$\endgroup\$ – Finbarr Dec 13 '17 at 17:24
  • \$\begingroup\$ @Finbarr Thanks for replying. I will do that. One more thing. What's the performance of using a 3.5mm jack vs directly plugging the wires in the breadboard? \$\endgroup\$ – Desperado Dec 13 '17 at 17:38
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    \$\begingroup\$ No. The resistors are there to bias the ADC input to the midpoint of the converter range (I don't know this particular board but it's likely to be 3.3V, 5V or a separate analogue reference - you'll need to check). The capacitor blocks the DC bias voltage from getting to the phone output. The components will actually form a high pass filter with a cutoff of around 30Hz, which is no bad thing. \$\endgroup\$ – Finbarr Dec 14 '17 at 11:51

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