Joystick mouse with the Pocketbeagle 2

I turn a Pocketbeagle2 into a mouse

jeremybobbin

@jeremybobbin·Apr 19, 2026· 2 min read·beaglebone

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I have a Pocketbeagle2 with a breakout board & a joystick. I wanted to make another "trackpoint" mouse.

To start, I had to flash BeagleBone's Debian image onto a microSD card. I plugged my microSD card into my laptop & used lsblk to find the name of it. In my case, it was called mmcblk0, so I ran the following to download, decompress & flash the card:

curl https://files.beagle.cc/file/beagleboard-public-2021/images/pocketbeagle2-debian-13.3-iot-v6.19-k3-arm64-2026-02-12-8gb.img.xz |
	xzcat |
	sudo dd of=/dev/mmcblk0 bs=1M

I connected the board to my laptop & I usually run dmesg | grep tty to see where a TTY is available. I saw the following output:

[    0.095257] printk: legacy console [tty0] enabled
[    4.979923] systemd[1]: Created slice Slice /system/getty.
[88779.759795] cdc_acm 2-1.1:1.2: ttyACM3: USB ACM device

The last line indicated to me that there is a TTY device available called ttyACM3, so I ran the following to get a TTY:

sudo picocom -b 115200 /dev/ttyACM3

I used the default username, debian, and password tmppasswd to log in & then proceeded to reset the password.

Since my goal was to use an analog joystick, I needed to figure out how to get the values from the analog pins, seen in the diagram below(P1.19, P1.21, P1.23, etc):

I had found a repository featuring example projects using the Pocketbeagle2. This file pointed me to an analog-to-digital converter device called ad7291 .

I found the device directory with grep ad7291 /sys/dev/char/*/name. In that directory, I found in_voltage[0-7]_raw. 8 files with number values in them:

debian@BeagleBone:~$ cat /sys/dev/char/236:0/in_voltage[0-7]_raw
2056
1940
1927
1887
1886
8
1927
1957

I connected P1.19 to ground & saw in_voltage0_raw dip to 0. I connected in_voltage0_raw to the 3.3V & saw it reach 4000. This is exactly what I needed. I then wired everything up:

For controlling my laptops cursor, I was thinking of just writing some commands over SSH. For that, I needed to get them connected over IP over USB.

I saw that the USB device was given the IP 192.168.7.2/24

debian@BeagleBone:~$ ip -br a
lo               UNKNOWN        127.0.0.1/8 ::1/128
dummy0           DOWN
usb0             UP             192.168.7.2/24 fe80::647:7ff:fe2d:cb76/64
docker0          DOWN           172.17.0.1/16

So I gave my corresponding device(enp0s26u1u1) an address in the same subnet:

sudo ip addr add 192.168.7.1/24 dev enp0s26u1u1
sudo ip link set up dev enp0s26u1u1

Once they were able to reach eachother over the network, I came up with the following script to take the analog values & control my laptop's cursor over SSH:

(
        echo export DISPLAY=:0
        while :; do
                read x < /sys/dev/char/236:0/in_voltage1_raw
                read y < /sys/dev/char/236:0/in_voltage2_raw
                x=$(( +1 * (x-2000) / (50) ))
                y=$(( -1 * (y-2000) / (50) ))
                echo xdotool mousemove_relative -- $x $y
                sleep 0.04
        done
) | tee /dev/stderr | ssh jer@192.168.7.1