Hi,
The overview diagram for the 6-mic array shows a jumper which appears to allow the use of the GPIO clock instead of the on-board 24MHz oscillator.
I have an application which requires the DAC clocks on the microphone array to be phase locked with the RPi clock, so I would like to be able to use this feature. Does anyone have any pointers for what to do to use this feature?
6-mic array using GPIO clock
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colin.dente
- Pre-kindergarten
- Posts: 2
- Joined: Wed May 29, 2019 7:11 pm
Re: 6-mic array using GPIO clock
Hi there,
here is the schematic related with mclk_en. thanks.
here is the schematic related with mclk_en. thanks.
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colin.dente
- Pre-kindergarten
- Posts: 2
- Joined: Wed May 29, 2019 7:11 pm
Re: 6-mic array using GPIO clock
Thanks for that Bill.
I think that the 2520 type oscillator sets its output to high impedance when enable is low, so I should be able to put in the missing link, drive MCLK_EN low, and then drive GCLK from the Pi. My only question is whether a 24MHz clock is feasible to send over the GPIO connector. I know that the AC108 has many possible input clocks. Could you advise on how to program its PLL for a lower frequency clock input?
Colin
I think that the 2520 type oscillator sets its output to high impedance when enable is low, so I should be able to put in the missing link, drive MCLK_EN low, and then drive GCLK from the Pi. My only question is whether a 24MHz clock is feasible to send over the GPIO connector. I know that the AC108 has many possible input clocks. Could you advise on how to program its PLL for a lower frequency clock input?
Colin