Kernel doesn't detect Aeotec Z-Stick Gen5 on Raspberry Pi 4


After rebooting my system Z-wave is not working anymore! I noticed there is no /dev/ttyACM0 anymore.

$ ls -l /dev/tty*
crw-rw-rw-    1 root     root        5,   0 Feb  9 08:07 /dev/tty
crw-rw----    1 root     audio     204,  64 Feb  9 08:07 /dev/ttyAMA0

Also, the device is not shown with lsusb.

$ lsusb 
Bus 001 Device 001: ID 1d6b:0002
Bus 001 Device 002: ID 2109:3431
Bus 002 Device 001: ID 1d6b:0003
Bus 001 Device 003: ID 1781:0c30

There is nothing in dmesg when I connect the device to the USB port indicating it is not detected by the kernel. When connecting the USB stick to my laptop everything works as expected, so there is nothing wrong with the stick itself.

The USB stick uses cdc_acm.ko driver. Not sure if it is compiled in to the kernel or as module? Anyways, lsmod doesn’t show it.

I’m a bit confused, since this has been working perfectly until the reboot. Any clues anyone?

I’m running on a Raspberry Pi 4.

$ hassio info
arch: armv7
channel: stable
hassos: "3.9"
homeassistant: 0.105.2
hostname: hassio
logging: info
machine: raspberrypi4
supervisor: "199"
- armv7
- armhf
timezone: Europe/Stockholm
 $ hassio hw info 
    - chan_id: "0"
      chan_type: digital audio playback
    - chan_id: "1"
      chan_type: digital audio playback
    - chan_id: "2"
      chan_type: digital audio playback
    name: bcm2835_alsa - bcm2835 ALSA
    type: ALSA
- /dev/mmcblk0
- /dev/mmcblk0p3
- /dev/mmcblk0p7
- /dev/mmcblk0p4
- /dev/mmcblk0p2
- /dev/mmcblk0p5
- /dev/mmcblk0p6
- /dev/mmcblk0p8
- /dev/mmcblk0p1
- gpiochip0
- gpiochip100
- gpiochip504
input: []
- /dev/ttyAMA0

There’s a known issue with the Aeotec stick and the Raspberry Pi 4… try using a USB 2 hub

1 Like

Great! That was it! I connected it through a USB hub and now it’s detected!

It’s weird that I initially had it working without the hub, but I guess that was pure luck maybe?

Thanks for the help!

1 Like

hi which hub did you bought
having the same issue

Is this still required with HASS OS 5.x? I’m referring to the need to use a hub to connect a Aeotec Z-Stick

It’s not a software but a hardware issue. So yes, unless you bought one of the new fixed versions of the stick or you fixed it yourself with a little hardware mod.

Hi @HeyImAlex, what is the hardware mod? Are we talking about soldering or something? Thank you for the quick response. Just curious what my options are to get rid of the USB hub,.

I edited my reply above with the link. There is an incorrect pullup resistor you need to fix. There is a little SMD soldering involved.