Mic / headphone on gpio pins?

Started by nickehallgren, January 13, 2015, 11:01:22 AM

Previous topic - Next topic

nickehallgren

Hi,

I have the A20 Micro and I was wondering if I can access the mic and headphone from GPIO ports (for testing some ideas)? If it is possible can the same be done on the A20 Lime 2 or must I use a usb soundcard on that?

Best regards
Nicke

Gerrit

Its is described in the manuals for both the Micro and the Lime

Microphone signals are: MICIN1 and VMIC
Headphone signals are: HPOUTL, HPCOM and HPOUTR

for the Micro only at the 3.5 mm phone connectors, for the Lime and Lime2 at the gpio-1 connector.

LINEINR and LINEINL are on GPIO connectors for both types

nickehallgren

Thanks Gerrit, yes I saw them but got confused when I found MIC1OUT_P & _N so I wanted to check what to use.

But to be able to use the mic and headphones on the Lime 2 I need to add the components found on page 27 in https://www.olimex.com/Products/OLinuXino/A20/A20-OLinuXino-MICRO-4GB/resources/A20-OLinuXino-Micro.pdf because the signals on the GPIO are directly connected to the processor, right?

Gerrit

Quote from: nickehallgren on January 14, 2015, 09:46:01 AM
But to be able to use the mic and headphones on the Lime 2 I need to add the components found on page 27 in https://www.olimex.com/Products/OLinuXino/A20/A20-OLinuXino-MICRO-4GB/resources/A20-OLinuXino-Micro.pdf because the signals on the GPIO are directly connected to the processor, right?

It would be good practice to both protect the headphone/mic and the board, with the mic it also depend if you need to power it or not, when not you only need MICIN1