Orange Pi Zero Microphone Pinout?

dookiedookie · Published in 2016-12-11 12:16:00

Hello everyone, I've looked at the microphone pinout pictures and I can't seem to get my Mic to work. I have several 3.5mm PC microphone with a 3-pole tip. I have several 3.5mm female jacks and I've tried jumpering them directly to the orange pi zero. Unfortunately I'm not familiar with Mic pinouts. The microphones work just fine plugged into a Usb soundcard attached to the Opi Zero. When I plug it into the headers, it can barely pick up my voice speaking directly into the mic. I've tried arecord, alsamixer (trying to boost the mic) etc. I've been using this command to test the mic with different wire hook ups: arecord -f S16_LE -r48000 -c2 -D hw:0 -F0 --period-size=1024 -B0 --buffer-size=4096 | aplay -D hw:2 - (Microphone is hardware 0 whereas my speaker is connected to my usb soundcard at the moment.)
Mic-Bias
Mic1P (Mic positive??)
Mic1N (Mic Negative??)

What would these pins connect to on a 3.5mm Microphone such as
http://www.banggood.com/Collar-M ... ching-p-978801.html
http://www.banggood.com/Wholesal ... pe-MSN-p-44253.html

Does it need a preamp? Does it need to be grounded? I'd prefer to use the onboard Mic pins so I don't have to use a usb soundcard (with mic and sound.)

Thanks!

shooreg · Published in 2016-12-12 22:45:36

Edited by shooreg at 2016-12-12 17:49

If there are 3 conductors then one of the lines is bias voltage:

With Bias Voltage (standard TRS for typical PC microphones)

As for microphone pins, look here: Expansion_Port

dookiedookie · Published in 2016-12-13 07:30:48

Edited by dookiedookie at 2016-12-13 07:33

shooreg replied at 2016-12-12 22:45
If there are 3 conductors then one of the lines is bias voltage:

With Bias Voltage (standard TRS f ...

Thanks shooreg, unfortunately it doesn't work with any microphone I have. I'm not sure if I need to boost the mic. I've played with alsamixer, sox, etc. I can't get it to pick up my voice unless I'm basically touching it to my face. The microphones work perfectly connected to a usb soundcard (syba card.) So I'm not sure.

Edit: and it BARELY picks up my voice. I'm not sure if it needs something like a pre-amp or what. Using Armbian latest nightly (if that helps.)

haiqu · Published in 2016-12-13 15:31:07

It's set up for an electret capsule mic, see the new expansion board.

shooreg · Published in 2016-12-13 21:18:11

The expansion board (as seen from foto on aliexpress) does not have any boost schematics - just some RC filters and has a mic soldered onto it - no way to replace it with a jack.

dookiedookie · Published in 2016-12-14 00:00:26

Thanks all, I tried jumpering an electret mic to the pins, but had the same results. Is there a schematic of the expansion board? I'll probably end up purchasing a few, I was just hoping to not have to wait to get the mic working. Thanks again.

shooreg · Published in 2016-12-15 16:40:43

At the end of this page there is a link to OPI Zero schematic, but not for the expansion (yet?) The same for wiki
What you can do, is to contact zhao_steven@263.net (Consulting service) or try to ask a seller on aliexpress