Turn my Raspberry Pi 0W into a bluetooth HID gamepad

[frowngo]

Hello there !

I've been trying to get through this for weeks... many projects are quite similar but I have never found one that answers my problem.

As the title says, I want to turn my Raspeberry Pi 0 W into a bluetooth HID gamepad.

I figured out that another way is possible. Indeed you can create your own bluetooth HID device with either the Adafruit BlueFruit Ez-Key or a the RN-42 module (or even the HC-05 with the RN-42 firmware). But I want neither of these solutions.

I want to use my Raspberry Pi 0 W in a way that it will be recognized as a bluetooth gamepad. Creating the gamepad is fine, I used the GPIO of the Pi for the inputs.

But once the gamepad is physically done, how to make my Pi appear as a gamepad ? I've seen that you can use hciconfig in the terminal of Raspbian in order to change the class of the Pi and set it as a gamepad but I must admit that I didn't understand everything.

And it's important that it appears as a gamepad and not as a keyboard.

In a nutshell, I would like to turn my old wired nes controller in a bluetooth one, and play on another Pi where Retropie is installed.

Thank you in advance if someone takes his time to help me with this because I can't take it anymore haha !

[MileSacul]

While I am by far no expert with Bluetooth, I think you need to set the hciconfig class.

man hciconfig states this for class:

       class [class]
              With no class, prints class of device. Otherwise, sets class of device to class.  class is a 24-bit hex number describing the class of device, as specified in section 1.2 of  the
              Bluetooth Assigned Numers document.

You can find this at hciconfig (1) - Linux Man Pages

I found a list of classes at BlueTooth's Baseband page.

In Table 9: The Peripheral Major Class keyboard/pointing device field it uses this bit config

5	4	3	2	Minor Device Class bit no. of CoD
0	0	0	1	Joystick
0	0	1	0	Gamepad

And Minor Device Class field - Toy Major Class has this:

7	6	5	4	3	2	Minor Device Class bit no. of CoD
0	0	0	1	0	0	Controller
0	0	0	1	0	1	Game

If this helps, here is how I get BlueTooth information from a connected device:

pi@lucaspi:~ $ hcitool con
Connections:
        > ACL **00:26:43:66:A8:74** handle 11 state 1 lm SLAVE
pi@lucaspi:~ $ hcitool info **00:26:43:66:A8:74**
Requesting information ...
        BD Address:  00:26:43:66:A8:74
        OUI Company: Alps Electric Co., Ltd (00-26-43)
        Device Name: PLAYSTATION(R)3 Controller
        LMP Version: 2.0 (0x3) LMP Subversion: 0x131f
        Manufacturer: Cambridge Silicon Radio (10)
        Features: 0xfc 0x07 0x82 0x7e 0x08 0x18 0x00 0x80
                <encryption> <slot offset> <timing accuracy> <role switch>
                <hold mode> <sniff mode> <park state> <RSSI> <channel quality>
                <paging scheme> <broadcast encrypt> <EDR ACL 2 Mbps>
                <EDR ACL 3 Mbps> <enhanced iscan> <interlaced iscan>
                <interlaced pscan> <inquiry with RSSI> <AFH cap. slave>
                <AFH cap. master> <AFH class. master> <extended features>

Try connecting your pi 0 to your other pi/debian system and see what info is different.

Lastly, maybe check out Bluetooth CoD: Bluetooth Class of Device/Class of Service Explained for information on CoD info. I will be reading this as well for one of my projects, so I might be able to provide more info.