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CC8520: I2C Master Control of Audio Codec

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Replies: 11

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Part Number: CC8520

Hi,

I am trying to add a feature to my design that allows an external microphone to become the audio source when it's plugged in, and an internal microphone will be the audio source otherwise.

The way I want to implement this is to wire each microphone to a different input on my audio codec (TLV320ADC3101).  Then when some detection circuit identifies the external mic has been plugged in, an I2C command would be sent to the codec to program the registers to switch the input source.

I currently have the codec under control of the CC8520 (I2C Master), so the ADC3101 is just sent some "State Configuration Sequences" to turn it on.  I don't know how the CC8520 could command it to switch from "ON, Mic input A" to "ON, Mic input B".

The CC8520 is in EHIF mode under control of a microprocessor.  Is my only option to make the TLV320ADC3101 a slave of the microprocessor?  Or does the CC8520 have some way to do this?

Thanks,

Arthur

  • In reply to M-W:

    M-W,

    Please let me review a strategy with you and see if I understand

    1) Our CPU tells the CC85xx to go to SR-SWITCH mode. Now the CC85xx is sourcing clocks to the Codec, but the CC85xx isn't trying to transmit audio.
    2) Our CPU sends the I2C configuration sequence to the codec.
    3) Our CPU tells the CC85xx to switch to ACTIVE mode. Now we're ready to send valid audio over the air.

    With this flow, there is no GPIO signalling required, the CPU just gets to decide when it's ready to move the CC85xx to the next state.

    How do we move between the states in section 3.5.3 via EHIF commands?

    Thanks,
    Arthur