AEOTEC USB Zwave module not creating /dev/ttyACM0

[ghost]

When i connect one of these:

https://www.amazon.co.uk/Aeotec-Z-Stick-Z-Wave-create-gateway/dp/B00YETCNOE

I normally get this device:

/dev/ttyACM0

which is used for serial comms to zwave home automation via home assistant.

Connecting it to the Pi4 + Buster i see no such device, infact when i connect via lsusb i see no change before / after connecting.

Any ideas?

[pelwell]

Do you get the same lack of results in the USB2 and USB3 ports?

[ghost]

Yes. I tried both usb2 and usb3 and I'm using a genuine pi 4 for power supply.

[pelwell]

Are there any relevant messages in the kernel log? Unplug the device, sudo dmesg -C (to clear out the old messages), plug it in, wait a moment, then dmesg > usb.txt.

[ghost]

Hmm - i tried a fresh install of buster and got this:

[ 398.804524] usb 1-1.1: new full-speed USB device number 4 using xhci_hcd
[ 398.941260] usb 1-1.1: New USB device found, idVendor=0658, idProduct=0200, bcdDevice= 0.00
[ 398.941278] usb 1-1.1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[ 399.010369] cdc_acm 1-1.1:1.0: ttyACM0: USB ACM device
[ 399.012948] usbcore: registered new interface driver cdc_acm
[ 399.012958] cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters

and i see /dev/ttyACM0

something is odd about my original install, when i try it on that install i get nothing appearing.

Let me reinstall HA over the weekend and i'll report back.

Thanks!

[pelwell]

"HA"?

[ghost]

HA - Home Assistant. It uses zwave via the serial port /dev/ttyACM0

[ghost]

ok so.... i tried my "fresh" install and i can't recreate that message above. Seems very temperamental. I wonder if its power related.

[pelwell]

Hmm - it could be power related, but I would expect some kind of response to a device insertion, not nothing.

[ghost]

Hmm - I tried the MicroSD card which wouldnt work on the Pi4 on my Pi3B+ and works flawlessly, plugged in + out + in + out....

81.081896] usb 1-1.3: new full-speed USB device number 6 using dwc_otg
[ 81.215187] usb 1-1.3: New USB device found, idVendor=0658, idProduct=0200, bcdDevice= 0.00
[ 81.215205] usb 1-1.3: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[ 81.289184] cdc_acm 1-1.3:1.0: ttyACM0: USB ACM device
[ 81.290193] usbcore: registered new interface driver cdc_acm
[ 81.290201] cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters
[ 95.383586] usb 1-1.3: USB disconnect, device number 6
[ 102.641555] usb 1-1.3: new full-speed USB device number 7 using dwc_otg
[ 102.774812] usb 1-1.3: New USB device found, idVendor=0658, idProduct=0200, bcdDevice= 0.00
[ 102.774830] usb 1-1.3: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[ 102.775964] cdc_acm 1-1.3:1.0: ttyACM0: USB ACM device
[ 110.231628] usb 1-1.3: USB disconnect, device number 7
[ 115.331396] usb 1-1.3: new full-speed USB device number 8 using dwc_otg
[ 115.464944] usb 1-1.3: New USB device found, idVendor=0658, idProduct=0200, bcdDevice= 0.00
[ 115.464962] usb 1-1.3: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[ 115.466096] cdc_acm 1-1.3:1.0: ttyACM0: USB ACM device

[ghost]

I thought I would check with aeotec as to the certification of the pi4 am I mentioned to check if a module is loaded, they said:

---

​We have tested using RPi V3 in this case, but we have not yet tested RPi 4. One item to absolutely make sure is that the cdc acm module is installed from the Linux kernel which is required to actuate as a ttyACM0 device. I'll look into acquiring a RPi V4 to see if i can find any issues here.

Cheers,
Chris Cheng
Field Application Engineer
Aeotec Inc.
www.Aeotec.com

I'm going to test more over the weekend, any ideas about the module they mentioned?

[pelwell]

The module is in Raspbian images - see your kernel logs above.

Can you try connecting via a powered hub?

[ghost]

I currently only have the official raspberry pi 4 power supply, can you recommend a powered hub? I'll buy one. Thanks!

[pelwell]

I wasn't expecting you to buy one, especially since I don't know if power is the cause of the problem, but the general rule of thumb round here is that Amazon Basics cables and adapters are safe bets.

[bieniu]

I had exactly same issue on RPi 3B after upgrade kernel to version raspberrypi-kernel_1.20181112-1 (November 4). Downgrade kernel fixed the issue. I haven't updated the kernel since then.

[ghost]

I had exactly same issue on RPi 3B after upgrade kernel to version raspberrypi-kernel_1.20181112-1 (November 4). Downgrade kernel fixed the issue. I haven't updated the kernel since then.

interesting but but i am guessing i can't do that with the PI4?

[bieniu]

interesting but but i am guessing i can't do that with the PI4?

I think not.

[ghost]

so... I found something interesting. If i connect it to one of the USB 2 ports (i tried all four actually) i get nothing in the dmesg logs.

but then when i connect a four port hub (that could be powered - but isnt) i see these:

[ 1269.486927] usb 1-1.4: new high-speed USB device number 15 using xhci_hcd
[ 1269.617433] usb 1-1.4: New USB device found, idVendor=1a40, idProduct=0101, bcdDevice= 1.11
[ 1269.617448] usb 1-1.4: New USB device strings: Mfr=0, Product=1, SerialNumber=0
[ 1269.617461] usb 1-1.4: Product: USB 2.0 Hub
[ 1269.618998] hub 1-1.4:1.0: USB hub found
[ 1269.619082] hub 1-1.4:1.0: 4 ports detected
[ 1270.046942] usb 1-1.4.1: new high-speed USB device number 16 using xhci_hcd
[ 1270.277312] usb 1-1.4.1: New USB device found, idVendor=1a40, idProduct=0101, bcdDevice= 1.11
[ 1270.277327] usb 1-1.4.1: New USB device strings: Mfr=0, Product=1, SerialNumber=0
[ 1270.277340] usb 1-1.4.1: Product: USB 2.0 Hub
[ 1270.278633] hub 1-1.4.1:1.0: USB hub found
[ 1270.278720] hub 1-1.4.1:1.0: 4 ports detected

then when i connect the Aeotec USB stick to one of the back two USB ports I then see:

[ 1329.418219] usb 1-1.4.1.1: new full-speed USB device number 17 using xhci_hcd
[ 1329.654873] usb 1-1.4.1.1: New USB device found, idVendor=0658, idProduct=0200, bcdDevice= 0.00
[ 1329.654890] usb 1-1.4.1.1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[ 1329.657705] cdc_acm 1-1.4.1.1:1.0: ttyACM0: USB ACM device

It now works 100% of the time.

odd

So your suggestion of using a hub @pelwell you might be onto something.

[pelwell]

I think the Pi budget will stretch to one of these - I'll get one on order.

[ghost]

ok cool - I'm sure its something simple but from what i've read about this stick a few people have reported that updated BIOS on NUC PCs has fixed similar issues so maybe this is firmware related.

i remember seeing something similat with the pi2s back in the day and @ghollingworth i think helped fix it - some kind of timing issue with usb (I sent my hub in and they put it into some kind of usb tool.

anyway - i'm up and running with ZWave, Home Assistant and a super cool Pi4 now 💯 :)

[ghost]

By the way I happend to notice this article which talked about new firmware changes to the USB chip, could this issue be fixed as part of those changes?....

https://www.tomshardware.com/news/raspberry-pi-4-firmware-update-tested,39791.html

[pelwell]

I'm expecting the ZWave module to arrive any day now so I'll be able to try the new firmware, but I wouldn't expect it to fix this issue. Plus, the power saving features are causing problems with some devices. However, that mainly seems to affect high throughput to SSDs, etc., and it is possible to revert to the original version, so feel free to try for yourself: https://www.raspberrypi.org/forums/viewtopic.php?f=28&t=243500&p=1490467#p1490467

[daaaaan]

I can confirm the new firmware doesn't help the issue.

Mine exhibits the same behaviour as above, tho don't have a hub to test.

[P33M]

Looking at some USB analyzer traces, the zwave module doesn't even signal a USB attach event. On a VLI expansion card in a PC, I see an attach event but spurious SE1s (illegal bus states) which makes me think that there's some oddness in the way the device is pulling D+/D-. Will require probing with a scope to find out what is happening.

[daaaaan]

Not sure if its relevant but on the rpi3 my stick exhibits no issue.

[ghost]

This is the USB hub that when I connect it to the pi 4 and the zwave USB device everything works fine:

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F283514195231

[systemofapwne]

I might have a similar problem with a "WiMOD iM871A-usb". Whenever I plug in the stick, a new device is created in /dev. That stick has been configured to receive W-MBUS data. On my PC, it shows me data popping in when I connect to it via putty. But on the pi4 with Raspbian Buster, if I do "cat" on that device, the output is quiet (while on stretch, it was outputting received data).
I could reproduce a similar behaviour with a self-made "nano-cul" stick.
Error was on my end - Had to rebuild some node-js libraries.

[pelwell]

There is something peculiar electrically about the Zwave dongle. When you plug it into the Pi 4 (through a USB analyser) the Pi tries to talk USB3 to it, and gets no response because the device is only USB2-capable. This shouldn't happen. Repeating the same test with a PC USB3 port as host you see the same USB3 chatter to start with, then after a few hundred milliseconds it falls back to USB3.

This suggests that the dongle has the electrical signature of a USB3 device and the VIA USB3 host controller doesn't get past that to try USB2. (I'm not sure that behaviour is required by the USB3 spec but it seems sensible)

[systemofapwne]

This is what I get with my stick:
[ 6951.473076] usb 1-1.4: new high-speed USB device number 8 using xhci_hcd
[ 6951.625698] usb 1-1.4: New USB device found, idVendor=05e3, idProduct=0610, bcdDevice= 6.54
[ 6951.625712] usb 1-1.4: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[ 6951.625723] usb 1-1.4: Product: USB2.1 Hub
[ 6951.625732] usb 1-1.4: Manufacturer: GenesysLogic
[ 6951.634230] hub 1-1.4:1.0: USB hub found
[ 6951.634533] hub 1-1.4:1.0: 4 ports detected
[ 6951.973078] usb 1-1.4.4: new full-speed USB device number 9 using xhci_hcd
[ 6952.130569] usb 1-1.4.4: New USB device found, idVendor=10c4, idProduct=ea60, bcdDevice= 1.00
[ 6952.130579] usb 1-1.4.4: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 6952.130587] usb 1-1.4.4: Product: WiMOD iM871A-usb
[ 6952.130594] usb 1-1.4.4: Manufacturer: Silicon Labs
[ 6952.130601] usb 1-1.4.4: SerialNumber: 00B93F17
[ 6952.146717] cp210x 1-1.4.4:1.0: cp210x converter detected
[ 6952.152214] usb 1-1.4.4: cp210x converter now attached to ttyUSB1

For this test, I connected it to a hub this time. Yet, it fails to work, even though it gets added to /dev: There is no serial throughput whatsoever.
Error was on my end - Had to rebuild some node-js libraries.

[systemofapwne]

Just to make sure, that I did not mess anything up when I upgraded from stretch to buster: I just flashed buster (lite) from iso (on a RPi4), made an apt-get update/upgrade/dist-upgrade and tried it again:
"sudo cat /dev/ttyUSB1" does not print anything, while this stick definitely receives data and is supposed to print it here. There is definitly something messed up.
Error was on my end - Had to rebuild some node-js libraries.

[fribse]

There is something peculiar electrically about the Zwave dongle. When you plug it into the Pi 4 (through a USB analyser) the Pi tries to talk USB3 to it, and gets no response because the device is only USB2-capable. This shouldn't happen. Repeating the same test with a PC USB3 port as host you see the same USB3 chatter to start with, then after a few hundred milliseconds it falls back to USB3.
This suggests that the dongle has the electrical signature of a USB3 device and the VIA USB3 host controller doesn't get past that to try USB2. (I'm not sure that behaviour is required by the USB3 spec but it seems sensible)

Wouldn't that fit with those that have used a hub in between, if it's a USB2 hub, that it will not get confused, and just go to USB2?

[kevin71246]

My experience & Fix:

Sabrent 4 Port Portable USB 2.0 Hub (9.5" Cable) for Ultra Book, MacBook Air, Windows 8 Tablet PC (HB-MCRM) WORKS with my USB3.0 External SSD drive in ALL ports (blue=usb3, black=usb2)

Onvian 3 Port USB Hub High Speed Splitter Plug and Play Bus Powered works if its the ONLY USB device. It does NOT work with my USB3.0 External SSD drive!

[bmorgan99]

Has anyone tried the pi4B?

[pelwell]

Everybody on this thread, I hope.

[bmorgan99]

oops. thought the B just came out

[poudenes]

On rpi4 work only with a hub between...

[rom1lenoir]

I think most of us have tested it on RPi4 on HomeAssistant. I also have a 'powerless' Sabrent 4 port USB3 hub, and for me with RPi4 and HASS.IO it works, but it sounds like it's a different setup than yours.

Strange that there'd be a difference; maybe the HA vs. OpenHAB access patterns are different enough that HA is able to keep it from dropping off the bus. Anyway, I'll see if I can find a plug for the Sabrent hub, or find something similar and powered, and report back for posterity.

@kelnos : did you find a way to get ride of the Z-stick disconnections?

[kelnos]

@rom1lenoir yes, I ended up getting this hub, which fixed the issue: https://smile.amazon.com/gp/product/B00L2442H0/

[dirksenrdh]

I think most of us have tested it on RPi4 on HomeAssistant. I also have a 'powerless' Sabrent 4 port USB3 hub, and for me with RPi4 and HASS.IO it works, but it sounds like it's a different setup than yours.

I am running Domoticz on the Pi4b.
exactly the same problem, I too solved it by using a archaic hub which I found somewhere in a drawer under a thick layer of dust.

[dirksenrdh]

Cost of the hub is not an issue but:

* I wanted to set up PI 4 on Sunday and it didn't work. I didn't have any hub on hand and the shops were closed so I couldn't do anything.

* Aeotec stick works on PI 3 and other devices (that I've tried)

* Adding a hub takes extra space and makes the whole setup more unwieldy.

* Seems like not all hubs fix the issue so trying to find one can be a trial and error

I can't agree more. All my Pi's are on a DinRplate on a DINrail. Putting the Aeotec stick on a 180 degree USB adaptor it all fits nicely in a cabinet.
with a hub and a separate powersupply (needs another wall socket) for the hub it directly is creating a mess.

[JamesH65]

All the posts in the world won't stop the fault lying with the Aeotec dongle...it's simply not USB compliant. Yes, it does work on some other devices - more by luck than anything else judging by my reading on this entire thread.

[pelwell]

As @P33M has said clearly, the Aeotec stick is non-compliant hardware. The fact that it works in some other host doesn't make it correct. Using a USB hub as an intermediary is a workaround, but nothing will fix the problem until Aeotec change their hardware.

[P33M]

As Github has helpfully collapsed the comment thread, including my comment immediately before I closed the issue where I detail what's wrong with the device, I'm posting it again:

• The Aotec Zwave dongle pulls D+ to +5V.
• Aotec's own testing confirms this is the case - see the pdf [0], test 1, point 1.
• This is done via a hardwired resistor on the dongle between VBUS and D+.
• This is a violation of the USB electrical specification. D+ should be pulled to 3.3V.
• The VIA chipset detects this state, and is activating an internal protection feature that appears to disconnect D+ and D- from the port.
• Hosts that do not implement protection of this nature will work with the device, but this may have impacts on long-term reliability as the signal is being constantly driven outside of specification limits.

[0] https://github.com/raspberrypi/linux/files/3634328/Z-Stick.RPi4.Electrical.Test.Results.pdf

[rchl]

Any DIY solutions that one with soldering iron could attempt?

[P33M]

On the gen 5 dongle, R33 is the pull-up from D+ to VBus. I tried removing it but apparently the MCU doesn't signal attach by itself. You could try soldering a replacement 1.5k resistor from the outermost pad of R33 to pin 8 of the on-board EEPROM as its vcc is 3.3v, but I don't recommend it.

[callagga]

just moved to PI4 and had this issue, then found this thread. Quick question - It it the case I should be able to plug in the Zwave Stick (gen 5) to the PI4 and then immediately on a terminal look for it appearing using say "df"? So whilst nothing changes for me now when I run "df" and plug it in then run "df", if I find a USB hub that works around the issue I should be able to tell immediately if it works using this method? thanks

[jsglazer]

Try ls /dev/ttyACM*
My Aeotec shows up on /dev/ttyACM0
I am using an old USB hub, will see if i can figure out which one

[callagga]

Try ls /dev/ttyACM*
My Aeotec shows up on /dev/ttyACM0
I am using an old USB hub, will see if i can figure out which one
Thanks. But just will this directory will it appear/disappear automatically as you plug/unplug the zwave stick?

[SirAthos]

/dev/ttyACM0 is not a regular file or directory, it's a device (and should appear when you plug in the USB stick).

A better command to use is lsusb. It will actually list USB devices, showing something like this:
Bus 001 Device 004: ID 0658:0200 Sigma Designs, Inc. Aeotec Z-Stick Gen5 (ZW090) - UZB

So if you're trying to write a script, you would do something like this:
lsusb | grep -q Aeotec && { echo "Found it!"; }

[callagga]

got it (/dev/ttyACM0) thanks

[fireball79]

hi, one question... i read all but i understand not the problem, but i´m lucky to see i´m not the only one. i tried to migrate my fhem to pi4 last year and it ends in so many trouble, that i throw this project away... now i see, it is a bug... but which one... a bug from the stick or rp4? i heard this bug is fixed in a newer revision from rp4?

thanks for feedback

[JamesH65]

We have made no changes, this is a fault in the Aeotec module itself. They need to fix their device.

[kmpm]

From the looks of their tech spec ( https://aeotec.freshdesk.com/support/solutions/articles/6000167094-z-stick-gen5-technical-specifications- ) there probably are sticks around that might be changed.
It looks as if there are 3 different versions. Just have to figure out how to get the one that I want.

Z-Stick Gen5
RPi4 compatible: Not without unpowered USB Adapter
Recommended USB Adapter with RPi4: Sabrent or Anker unpowered USB hub (2.0 or 3.0)

New Z-Stick Gen5
RPi4 compatible: Yes

Z-Stick Gen5+
RPi4 compatible: Yes

[pelwell]

Thanks - that's probably as close as we'll get to an admission from them.

[codyrobbins]

For anyone else looking into this problem, I contacted Aeotec based on the link posted above by @kmpm about different hardware revisions of the product. They told me that they do indeed have a new version that supports the Raspberry Pi 4. If you order it from Amazon or somewhere else you can’t be sure which revision you’re receiving, but you can order the latest one with Raspberry Pi 4 support directly from their online store here:

https://popp.to/products/aeotec-z-stick-gen5-zw090

The product description notes:

This is the 2020 upgraded model from Aeotec featuring compatibility with Raspberry Pi 4. Older models of ZW090 do not offer Raspberry Pi 4 compatibility.

[ghost]

Sorry for the late reply why but yes this is great news that there is a newer revision of the hardware which supports the pi 4.

I also inquired about an upgrade procedure and involved a backup and restore of the existing operational on the same stick I was provided with the following steps:

https://aeotec.freshdesk.com/support/solutions/articles/6000167023-how-to-use-z-stick-gen5-backup-software-backup-and-restore-

Finally I'll be able to get rid of my old USB hub!

[rchl]

On the gen 5 dongle, R33 is the pull-up from D+ to VBus. I tried removing it but apparently the MCU doesn't signal attach by itself. You could try soldering a replacement 1.5k resistor from the outermost pad of R33 to pin 8 of the on-board EEPROM as its vcc is 3.3v, but I don't recommend it.

I just found this post on how to make a hardware mod. Basically re-routing R33 to get voltage from VCC so as you said.
It's here: https://community.home-assistant.io/t/sticky-aeotec-z-stick-gen5-raspberry-pi4/218405
I haven't tried it myself (yet).

[Nadahar]

I just found this post on how to make a hardware mod. Basically re-routing R33 to get voltage from VCC so as you said.
It's here: https://community.home-assistant.io/t/sticky-aeotec-z-stick-gen5-raspberry-pi4/218405
I haven't tried it myself (yet).

I have, and it works perfectly. It's found instantly after doing the mod, and it's 100% stable. However, the resistor is extremely small, so the soldering is difficult. I managed to desolder it, but when I tried to pick it up with some tweezers, being so small, it "slipped" and flew away. It was simply impossible to find once you have lost sight of it. I would recommend anyone that wants to try the fix to get hold of a 1.5kΩ resistor in "normal size" first, so that they have that as a backup when the tiny one disappears. I had to improvise and use what I could find, so I ended up with 3x 390Ω and 1x 330Ω resistor in soldered in series. Not pretty, but it works great.