SAI Interface at i.MX processors

[danstu]

Hi,

I have some troubles to understand SAI Interface correctly. On Reference Manual the SAI external signals are described as follows:

At SAI1_RX_BCLK this can be an input when a I2S device is generating the clock or an output when i.MX is generating the clock? How is this to understand? What is then the SAI1_TX_BCLK for, it can do the same.

I want to connect a PCM Amplifier "MAX98357" and a I2S Microphone "ICS-43432".

My connection would be the following (Simultaneously use of mic and amplifier, so I use two separate SAI ports):

Microphone in I2S use:

SAI1_TX_BCLK -> SCK

SAI1_TX_SYNC -> WS

SAI1_RX_DATA -> SD

PCM Amplifier in I2S use:

SAI2_TX_BCLK -> BCLK

SAI2_TX_SYNC -> LRCLK

SAI2_TX_DATA -> DIN

Could I use the TX_BCLK or the RX_BCLK to generate the clock for my mic? This is a bit confusing.

Thanks for any help.

Regards,

Dani

[jamesbone]

Hello,

Let me try to put this way,   the signal it is an output, when you are going to use the i.MX as the Audio Generator,  not the case if you are going to connect the MIC in this case it is an Input and the MIC need to provide this signal clock.

So the way you are connecting the Audio Amplifier and the MIC with the i.MX it is correct. when you are going to use the Amplifier it is an output. when you use the MIC it is an Input.

Hope this clarifies.