I have a bit trouble here. I need to have a bluetooth device (preferably cheap) to be placed on my room. Then I want my buddy phone to pick up and pair with that bluetooth device. I have developed a program for Android that is basically to check if the phone is paired to the unique MAC address the bluetooth device have. The rest of the stuff will be handled by the program on the phone.

The trouble is: I can't find any bluetooth device that could run itself on a certain voltage (I dont mind any since its on a PSU) What I've tried so far is the USB Dongle. It won't work without being connected to the PC whatsoever. By it won't work, I mean I can't search for it in my buddy phone when it is not connected to a PC. Another thing is an A2DP Bluetooth Dongle. It works, but my buddy phone also goes to silent since all the audio output goes to the A2DP.

Anyone can help me find a bluetooth device that can run itself? I don't need re programmable stuff since it will be used only for verification.

Thanks in advance.

EDIT: "Questions seeking recommendations for specific products or places to purchase them" I never asked for places to purchase them, please re-read. I don't know what's wrong with the question. My goal in this question is just to find what works by sharing what didn't works to me. If I already known that "tiny board" thing is a HC-05 or in other name a Bluetooth Module or if that thing will work, I wouldn't ask. Just now I also discovered that they did include one of those HC-05 inside of my toolbox.

  • 1
    \$\begingroup\$ "USB Dongle [...] won't work without being connected to the PC" That's because dongles don't include a Bluetooth stack, just a radio. \$\endgroup\$ Jul 28, 2016 at 11:52
  • \$\begingroup\$ @IgnacioVazquez-Abrams Ah, now I see why it doesn't shows up in my buddy phone. \$\endgroup\$ Jul 28, 2016 at 11:57
  • \$\begingroup\$ Try HC-05 or any other simple Bluetooth device with SPP. \$\endgroup\$ Jul 28, 2016 at 14:18

1 Answer 1


If you just want a Bluetooth device so you can pair your phone (or any other Bluetooth device), you can use the FC-114 alias HC-05 device:

It's a very simple device that you can connect using 5V power supply. It is designed to connect a microcontroller to it via serial communication. Microcontroller is not mandatory if your sole requirement is to pair your phone to it.

Depending on firmware variation, its pairing code is 1234 or 0000.

Here is a connection diagram:

HC-05 as standalone device

There are a variety of manufacturers of HC-05 / FC-144. Depending on which one you buy, all devices in the same batch may share the same MAC address, which can be annoying depending on your application. These devices have so called AT-MODE which allows to configure them using a UART to transmit commands to the RxD/TxD connectors.

UART devices are available as embedded in a Microprocessor, or as a USB to UART adapter. As Ignacio mentions, command AT+BIND is able to set the Bluetooth address (See the communication protocol, page 10). I do not believe that the configured address is kept in Flash.

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    \$\begingroup\$ Grounding the RX connection of a UART is a bad idea since it is active low. \$\endgroup\$ Jul 28, 2016 at 12:17
  • \$\begingroup\$ Right. Wasn't thinking. \$\endgroup\$
    – jmgonet
    Jul 28, 2016 at 12:18
  • \$\begingroup\$ Will this work as you intended? This is the only thing I can find from typing HC-05 i.stack.imgur.com/qW7Pm.jpg or if dead link g01.a.alicdn.com/kf/HTB12rn5LVXXXXa3aXXXq6xXFXXXw/… \$\endgroup\$ Jul 28, 2016 at 12:24
  • \$\begingroup\$ I'm correcting the diagram after comment from Ignacio. It will allow you to pair your phone and nothing else. You're only interested in pairing, right? \$\endgroup\$
    – jmgonet
    Jul 28, 2016 at 12:27
  • \$\begingroup\$ @jmgonet Yes. I only need the phone to detect its unique MAC Address. Nothing else. Will the one that I posted works? \$\endgroup\$ Jul 28, 2016 at 12:29

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