HFP on Raspberry Pi

Update (Sep 7, 2017):
If you are using Raspbian Stretch, please refer here instead of steps below. This post below is for Raspbian Jessie.  

 

The purpose of this post is to enable Bluetooth Handsfree Profile (HFP) on Raspberry Pi so that Raspberry Pi can act like as a handsfree speaker phone or a handsfree car kit. There is one thing needs to be mentioned before start. The original plan was to use Raspberry Pi3’s on-board Bluetooth chip for this project. Unfortunately, it didn’t work. It seems that the problem is related with the chip. So, we have to use a Bluetooth dongle instead.

Here is the list of contents of this post.

Contents:
– Hardware Prerequisites
– Software Prerequisites
– Steps
1. Setting Up
2. oFono
3. PulseAudio
4. Connect your Phone
5. Make a Call!
– Conclusion
– Reference

Let’s get started.

 

Hardware Prerequisites
Since Raspberry Pi doesn’t have microphone input by default, it need to be added. In this post, I’ll use a USB sound card with a 3.5 mm jack microphone.

Also, as mentioned above, we’ll use a Bluetooth dongle instead of on-board Bluetooth chip.

Raspberry Pi3
– Bluetooth dongle (Panda Bluetooth 4.0 USB Adapter)
– USB Sound Card (SYBA USB sound adapter / FG-UAUDV1-C119)
– Microphone with 3.5 mm audio jack (e.g. HDE Mini 3.5mm Aux Auxiliary Voice Microphone)
– Speakers with 3.5 mm audio jack

 

Software Prerequisites
Below are the required versions to enable Bluetooth HFP according to PulseAudio release note.

– Bluez 5.0 (or later)
– PulseAudio 6.0 (or later)
– oFono 1.13 (or later)

 

Steps
1. Setting Up
1-1. Connect Bluetooth dongle and USB sound card with Raspberry Pi.
1-2. Connect the microphone and speakers to 3.5 mm audio jacks on the USB sound card.
1-3. Boot up Raspberry Pi Board. If it’s not set up yet, please refer this post.
1-4. As described, we don’t use on-board Bluetooth chip. So it needs to be disabled. To do that, open “/etc/modprobe.d/raspi-blacklist.conf”.

1-5. Add lines below and save.

1-6. Then reboot the board.

1-7. After reboot, check dmesg and make sure there is no Bluetooth-related errors.

1-8. Also, make sure hci0 is UP.

The result should be like this:

If it’s DOWN for some reason, then turn it up.

2. oFono
2-1. oFono is not installed by default, so let’s install it.

2-2. Make sure the version is 1.13 or later.

2-2. Then, start the service.

You can check the service running like below.

3. PulseAudio
Since the preinstalled PulseAudio is 5.0, it needs to be updated to at least 6.0.

3-1. Uninstall the current PulseAudio.

3-2. Open “/etc/apt/sources.list”.

3-3. Add the line below:

3-4. Execute commands below:

3-5. Update the package list.

3-6. Install PulseAudio and its Bluetooth module:

3-7. Check the version and make sure it’s 6.0 or later.

3-8. Open “/etc/pulse/default.pa”.

3-9. Add “headset=ofono” on the line of ‘module-bluetooth-discover’.

3-10. To enable echo canceling, add the lines below:

3-11. Start PulseAudio.

4. Connect your Phone
4-1. Launch bluetoothctl.

4-2. Then, input below commands.

4-3. Start searching your phone. Make sure your phone is discoverable.

4-4. After detecting your phone, turn scan off.

devices command shows a list of found devices.

4-5. Then, pair, trust and connect to your phone by specifying the Bluetooth device address (in this case it’s “XX:XX:XX:XX:XX:XX”, please replace it wity your device’s address).

If everything is ok, you should see “successful” at the end of the result for each command like below.

5. Make a Call!
To make a call, we’ll use oFono test scripts which is included in the source code.
5-1. First, download the source and extruct.

5-2. Then, you can make a call by:

If you want to end the call, then execute:

 

Conclusion
Thanks for all the forums and articles I referred, now HFP is working on Raspberry Pi!
Next, I’m planning to apply echo canceling and ambient noise suppression, maybe equalizer.

Update (June 22, 2017):
Added one step (step 3-10) to enable echo cancellation. It seems that ‘module-echo-cancel’ does not only echo cancellation but ambient noise suppression. I haven’t check the noise suppression yet but I think the echo cancellation is working well based on my brief testing.

 

Reference
– Connect Bluetooth Headset To Raspberry Pi 3 (A2DP & HSP)
http://youness.net/raspberry-pi/bluetooth-headset-raspberry-pi-3-ad2p-hsp

– PulseAudio 6.0 Release Notes –freedesktop.org
https://www.freedesktop.org/wiki/Software/PulseAudio/Notes/6.0/

– PulseAudio Documentation –freedesktop.org
https://freedesktop.org/wiki/Software/PulseAudio/Documentation/

– module-echo-cancel –freedesktop.org
https://www.freedesktop.org/wiki/Software/PulseAudio/Documentation/User/Modules/#index45h3

– Pulseaudio echo cancellation — Debian User Forums
http://forums.debian.net/viewtopic.php?f=16&t=128306

 

2 Comments

  1. When I attempt to execute:
    gpg –keyserver pgpkeys.mit.edu –recv-key 8B48AD6246925553
    gpg –keyserver pgpkeys.mit.edu –recv-key 7638D0442B90D010

    I get “failed to start the dirmngr: no such directory found”
    And
    “Keyserver receive failed: no dirmngr”

    Any advice?

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