Multi-purpose pin configuration for DMIC input with Eval-ADAU1787 board
Hi,
I am wondering if I can use multi-purpose pin MP12 for PDM mic input (DMIC45 or DMIC67). SigmaStudio hardware configuration allows to configure MP0 through MP8 for DMIC input, but not for MP9 through MP12.
1) Can I manually set up MP12 register for DMIC input? If so, how do I do?
2) Is there a particular reason I should NOT use MP9 - 12 for DMIC input?
Thank you
Hello,
That's a problem that we'll be fixing in a future release of SigmaStudio. There is a workaround: it's possible to use the sequencer window or Read/Write Window (accessed by right-clicking the ADAU1787 block in the Config tab of SigmaStudio) to directly write to the MP control register. See below for the address and bits to write in order to set MP12 as a DMIC:
Also from the datasheet, regarding MP11 and MP12:
"Care must be taken when using SELFBOOT/MP11 and SW_EN/MP12 as multipurpose pins. The states of these pins at power-up (later of either PD pin going high or power being applied with PD pin already high) determine whether the device self boots, which must still be followed even if the pins are used for another multipurpose function later. "
So, while there's no reason not to use these pins as a DMIC input, just be careful at startup to keep the pin in the desired mode until startup is complete, before starting to use it as a DMIC.
Hope this helps!
Best regards,
Tyler Krome
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