Extend Audio mic & speaker to Bluetooth earbud or headset

Yes, I used a hot air solder tool to desolder the RN-52 module on the SparkFun board, and soldered in it’s place a RN-52SRC module. I found it on Amazon. Newark and other vendors also sell them, Just Google search RN52SRC.
A further update…Once I replaced the chip and powered it up, it only partially worked. It was blinking normally ready to pair with but I could not communicate with the module as before using the RX and TX pins on the module to an FTDI/UART module to my computer serial port. I decided the chip was either defective or I got it too hot when soldering.
The RN-52SRC is hard to find. DigiKey lists only 6 available last time I looked. I decided to with to what I think is a better, new chip. Availability is better. It is the BC127 module. I down loaded data sheets from SparkFun and also Sierra Wireless, the chip maker. I also order Sierra Wireless’s development board. It’s all coming in a week or so. I was able to download from SparkFun the Eagle schematic and board for their old breakout board. I am going to make my own board for the Bluetooth BC127 with mic and audio out to work with the MOVI board audio, and will use the spark fun information to help me design the new board.
I’d be happy to share the final results, assuming it all works.
Bart

typo in above. I should read “decided to go” on first line of second paragraph.

Thanks again Bart!

Looking forward to your experiences here, very much and very much appreciated that you are willing to share.

I did a moderate injury to my leg and have not felt up to trying out that mic I mentioned above, I do not expect it to work :-(.

I have what is going to be the last mic I am going to try, an “array mic”, but at this point it is rather a shot in the dark and is going to be a problem space wise.

I think you have the right idea.

I’m wondering if the RC chip has the same pinouts as the straight 52, other than heat damage that is my best guess. Hate it when that happens.

More pills, leg up, back to bed!

Thanks again, V.

Hi Vic,
Sorry to hear your set back concerning your leg.
Yes, the RN52SRC has the same pinouts as the RN52.

The Bluetooth Development Kits BC127 arrived last night from DigiKey.
It came with no documentation, so I had to go to Sierra Wireless to get that.
I hope to try it out connected to the MOVI in the next couple of days.

Bart

Hi Bart,

I just ordered one from Digikey too.

With the happy pills that is about it for now :slight_smile:

Please keep me posted!

Thanks & take care, V.

Vic,
I think you will be happy with the Development Kit BC127. I found out the the RGEN button in the instructions (to trigger Regen into the mode (Source or Sink) you want) is the Pairing button. You can trace the circuit trace directly to pin 28 on the BC127 chip, which is the Regen pin.

Where do you live if I may ask? I’m in Snohomish, WA
Bart

Out of the box, I was able to stream music from my Mac as a source to the BC127 development kit.
I am having lots of trouble getting the board to go into source mode and cannot seem to communicate with the board either using my Mac in High Sierra, or Windows 10. I am getting error messages saying I don’t have permission. I’ve checked the port permissions to the device and they are chmod 666, wide open. So I have left a message asking for help on the Sierra Wireless forums board.

Things the manuals and videos don’t tell you… I am now using CoolTerm installed on my Mac.
The BC127 kit when connected to the USB UART port outputs 3 different usb ports.
One is called BC-XXXXXX-SPPDev-1, the other BC-XXXXXX-SPPDev-2, and finally usbserial-XXXXXXXX.

It turns out you must connect to the usbserial -XXXXXXXX port, then your usb to serial communications will work.

CoolTerm does work on Windows 10 but you have to tell Windows what com port to use and possibly download drivers before you can get it to work. The Mac was easier.

So now I am back to playing with it and trying to get it to Source rather than Sink.
Bart

Hi Bart!

The BC127 arrived and I got as far as getting the docs from Sierra Wireless (awful web site and you will register to get at the docs…).

Between taking care of Jean and my exciting adventures with the Doctor and my leg, I’m not sure how soon I can get to it.

The last two mic also arrived and I did get a little time to putz with those to no more avail than any of the others piled in the mic box :-).

Please do keep me posted!!

Thanks, V.

Hi Vic,
I finally did get the BC127 module to source, and connected my bluetooth earbud to it. That is, I was able to get it to pair. However, I am not able to hear anything coming from the mic input on the BC127. I was reading on the Sierra Wireless forum which I have joined, and saw someone trying to do what I want to do, and a experienced poster (mlw) was telling the guy, you can’t do what he wanted to do because a smart phone needed to be present to do the audio switching or something like that. I wrote him and asked if that were true, that two way audio communication between the BC127 and an earbud had to be controlled by a smart phone. And if it were true, could I used an Arduino cpu instead of the smart phone to handle the communication. We will see what he has to say. I hope the guy is wrong because then I would have to write more arduino code and wire directly to the BC127 module. So where are you located?

Hello, admin. Im a student doing final year project currently and i have some issues with movi external microphone, do you have any suggestions on microphone to work with movi? the in build microphone is not working very well therefore i want to add a external one but do not know what microphone is suitable, possible to give me some advice?

Hi Jinghung,

I’m not admin, but I had admin suggest the PoP voice Upgraded Lavalier lapel Microphone as found on Amazon at:
https://smile.amazon.com/PoP-voice-Microphone-Omnidirectional-Smartphones/dp/B075VQ7VG7/ref=sr_1_5?keywords=PoP+voice+Upgraded+Lavalier+Lapel+Microphone&qid=1568120509&s=gateway&sr=8-5

You can use the software option “recognizer.setThreshold(5);” to adjust the sensitivity.

You will loose the built in AGC (automatic gain control) that the built in mic has.

Bart

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Hello BartW,
Any update on the current status of Bluetooth headset/earbuds with MOVI?
Regards

Hi, No I have not had any success and quit trying after chasing several software engineers and not getting any help. I bought several Bluetooth modules capable of audio along with engineering test boards and tried to program them but could not get them to work. I would still love to get some help in that area but i am stumped.
It’s speculation on my part, but it is like a trade secret the industry does not want to let out because then anybody could make a cell phone, etc. that worked with a mic/earbud causing profitability to go down.