Need help for i2s use (pin assignment issue)

[Clement Treangle]

Hi everybody !

I am currently working on a speaker identification program, in using a Teensy 3.1.
For that, I am using a ADMP441, which works with i2s.

The fact is... Actually it is complicated. In the one hand, I would like to use pin 16 for I2S0_RXD0 and pin 17 for I2S0_RX_BCLK.
In the other hand, I would like to send the sample frequency directly via an other microcontroller, a msp430g2553 (or generate
the clock directly in the msp430, it would be easier).

Anyway, I saw that we could use i2s only with particular pins. So I wondered if it was possible to use pin 16 and pin 17, because
the other pins are already used for me...

Here are some schematics, for a better understanding.

ADMP441 schematic


MSP430G2553 schematic


Teensy schematic



I hope I have been clear in my explanations...

 

[PaulStoffregen]

I would like to use pin 16 for I2S0_RXD0 and pin 17 for I2S0_RX_BCLK.
.....
Anyway, I saw that we could use i2s only with particular pins. So I wondered if it was possible to use pin 16 and pin 17,

No, you can not use those pins.

I2S0_RXD0 is only possible on pin 13 (PTC5)

I2S0_RX_BCLK is only possible on pin 11 (PTC6) and pin 27 (PTC9)

I2S0_RXD1 is only possible on pin 13 (PTC11)

I2S0_TX_BCLK is only possible on pin 9 (PTC3) and pin 32 (PTB18)

because the other pins are already used for me...

I'm afraid your only option is to reassign pins. The chip simply doesn't offer those signals on pins 16 and 17.

 

[Clement Treangle]

Arf.. It was what I dreaded..
I will see if it possible to change the mapping, because I need to use SPI protocol too, in order to store the data I receive with the microphone.

Thank you for your quick answer.

 

[PaulStoffregen]

The SPI library has functions to reassign its pins. See the audio library examples.

https://github.com/PaulStoffregen/Audio/blob/master/examples/PlayWavFromSdCard/PlayWavFromSdCard.ino

 

[Clement Treangle]

Ah ok !
And is it possible, for example, to assign to the pin 17 SPI_CLK ? And for the pin 16 SPI_DOUT ?
Because I don't use these pins at all, I need only the pins 18 and 19 for I²C.

 

[PaulStoffregen]

Ah ok !
And is it possible, for example, to assign to the pin 17 SPI_CLK ? And for the pin 16 SPI_DOUT ?

Please refer to this pinout card (a printed copy should have been included with your Teensy) for what capabilties each pin can have.

 

[Clement Treangle]

Ok, I will try to fix that. Thank you again for your answers !