How to use an AnyTone Bluetooth PTT BP-02 button with a computer

How to use the python script

The script is very simple. It waits for your ptt button to connect to your computer (by pressing on the button) then send space when pressed.

Setup

If you don’t want to mess up your system, you can use a venv, otherwise you can just pip3 install:

$ python3 -m venv venv_ble
$ . venv_ble/bin/activate
$ pip3 install BLE_GATT
$ pip3 install pyautogui

Usage

Just run ptt_gatt.py in a terminal window and keep it open while you operate with your favorite piece of software. It works well with SparkSDR.

$ ./ptt_gatt.py

Press ^C to quit.

What to do if your PTT button does not have the same mac as mine

The script is hardcoded with 00:1B:10:60:B0:2A as bluetooth mac. If your PTT button has a different mac address, you have to find it and replace it in the script. Here is how to find it using bluetoothctl:

$ bluetoothctl
Agent registered
[CHG] Controller B4:69:21:14:8E:DE Pairable: yes (1)
[bluetooth]# scan on (2)
Discovery started
[CHG] Controller B4:69:21:14:8E:DE Discovering: yes
[CHG] Device 00:1B:10:60:B0:2A RSSI: -77 (3)
[CHG] Device 00:1B:10:60:B0:2A Name: ELET-PTT60B02A (4)
[CHG] Device 00:1B:10:60:B0:2A Alias: ELET-PTT60B02A
[CHG] Device 00:1B:10:60:B0:2A ManufacturerData Key: 0x5045
[CHG] Device 00:1B:10:60:B0:2A ManufacturerData Value: 54 54 c0 53 72 64

This is my bluetooth device on my laptop
Scan for devices around
Very quickly we found a new device with a received signal strenght indicator of -77dB, with its mac address
The name of the device found, again with its mac address

You might find some other devices. The one you’re interested in should have a very similar name, if not the same.

Once you have the mac address of your ptt button, edit the python script to reflect your setup and you’re in business!

How I found the magic uuid value

In the script all the magic happens here:

button.on_value_change(button_uuid, notify_handler)

But, how did I found the button_uuid value?

First, let’s query the device:

[bluetooth]# info 00:1B:10:60:B0:2A
Device 00:1B:10:60:B0:2A (public)
Name: ELET-PTT60B02A
Alias: ELET-PTT60B02A
Paired: no
Trusted: no
Blocked: no
Connected: no
LegacyPairing: no
UUID: Generic Access Profile    (00001800-0000-1000-8000-00805f9b34fb)
UUID: Unknown                   (0000ff01-0000-1000-8000-00805f9b34fb)
UUID: Vendor specific           (9e5d1e47-5c13-43a0-8635-82ad38a1386f)
ManufacturerData Key: 0x5045
ManufacturerData Value:
54 54 c0 53 72 64                                TT.Srd
RSSI: -69

Ok, it exposes a few uuids. Lets gather more information:

[bluetooth]# connect 00:1B:10:60:B0:2A
Attempting to connect to 00:1B:10:60:B0:2A
[CHG] Device 00:1B:10:60:B0:2A Connected: yes
Connection successful
[NEW] Primary Service (Handle 0x7461)
	/org/bluez/hci0/dev_00_1B_10_60_B0_2A/service0004
	0000ff01-0000-1000-8000-00805f9b34fb
	Unknown
[NEW] Characteristic (Handle 0x7461)
	/org/bluez/hci0/dev_00_1B_10_60_B0_2A/service0004/char0005
	0000ff02-0000-1000-8000-00805f9b34fb
	Unknown
[NEW] Descriptor (Handle 0x1eb4)
	/org/bluez/hci0/dev_00_1B_10_60_B0_2A/service0004/char0005/desc0007
	00002902-0000-1000-8000-00805f9b34fb
	Client Characteristic Configuration
[NEW] Characteristic (Handle 0x7461)
	/org/bluez/hci0/dev_00_1B_10_60_B0_2A/service0004/char0008
	0000ff03-0000-1000-8000-00805f9b34fb
	Unknown
[NEW] Primary Service (Handle 0x7461)
	/org/bluez/hci0/dev_00_1B_10_60_B0_2A/service000a
	9e5d1e47-5c13-43a0-8635-82ad38a1386f
	Vendor specific
[NEW] Characteristic (Handle 0x7461)
	/org/bluez/hci0/dev_00_1B_10_60_B0_2A/service000a/char000b
	e3dd50bf-f7a7-4e99-838e-570a086c666b
	Vendor specific
[NEW] Descriptor (Handle 0x27f4)
	/org/bluez/hci0/dev_00_1B_10_60_B0_2A/service000a/char000b/desc000d
	00002902-0000-1000-8000-00805f9b34fb
	Client Characteristic Configuration
[NEW] Characteristic (Handle 0x7461)
	/org/bluez/hci0/dev_00_1B_10_60_B0_2A/service000a/char000e
	92e86c7a-d961-4091-b74f-2409e72efe36
	Vendor specific
[NEW] Characteristic (Handle 0x7461)
	/org/bluez/hci0/dev_00_1B_10_60_B0_2A/service000a/char0010
	347f7608-2e2d-47eb-913b-75d4edc4de3b
	Vendor specific
[CHG] Device 00:1B:10:60:B0:2A UUIDs: 00001800-0000-1000-8000-00805f9b34fb
[CHG] Device 00:1B:10:60:B0:2A UUIDs: 0000ff01-0000-1000-8000-00805f9b34fb
[CHG] Device 00:1B:10:60:B0:2A UUIDs: 9e5d1e47-5c13-43a0-8635-82ad38a1386f
[CHG] Device 00:1B:10:60:B0:2A ServicesResolved: yes
[CHG] Device 00:1B:10:60:B0:2A Alias: 00-1B-10-60-B0-2A
[CHG] Device 00:1B:10:60:B0:2A Name is nil

Ok wow, that’s a lot! Let’s go now to the GATT menu (where we can also list-attributes to get this list back if needed) to check what uuid is the right one:

[00-1B-10-60-B0-2A]# menu gatt
[00-1B-10-60-B0-2A]# select-attribute /org/bluez/hci0/dev_00_1B_10_60_B0_2A/service0004/char0005 (1)
[00-1B-10-60-B0-2A:/service0004/char0005]# notify on (2)
[CHG] Attribute /org/bluez/hci0/dev_00_1B_10_60_B0_2A/service0004/char0005 Notifying: yes
Notify started
[CHG] Attribute /org/bluez/hci0/dev_00_1B_10_60_B0_2A/service0004/char0005 Value:
  42 41 54 54 28                                   BATT(
<button press> (3)
[CHG] Attribute /org/bluez/hci0/dev_00_1B_10_60_B0_2A/service0004/char0005 Value:
  45 4c 45 54 31                                   ELET1
<button release> (4)
[CHG] Attribute /org/bluez/hci0/dev_00_1B_10_60_B0_2A/service0004/char0005 Value:
  45 4c 45 54 32                                   ELET2
[00-1B-10-60-B0-2A:/service0004/char0005]#

I’ve tried all the paths exposed, one by one, this is the one I wanted, hence the uuid of 0000ff02-0000-1000-8000-00805f9b34fb
notify on will show in the console events when something happens, like, for example, a button press :)
Here button was pressed
Button was released here