ebusd not acquiring signal

[CrazyPingvin]

Hi everyone,

I am using the ebus adapter v5 and connected it to the ebus port of my Vaillant ecoCompact VSC 206/4-5 and to the USB Port of my raspberry Pi1. This is the output of ebusctl info:

version: ebusd 23.3.23.3-5-g47d2a3aa
update check: revision 23.3 available
device: /dev/ttyACM0, serial high speed, enhanced
signal: no signal
reconnects: 0
masters: 1
messages: 11
conditional: 0
poll: 0
update: 4
address 31: master #8, ebusd
address 36: slave #8, ebusd

So apparently no signal is acquired.

Measuring with the multimeter one of the wires shows a signal of 21V while the other wire has no signal. The signal on the wire with 21V looks like this:

I doubt that this is how the ebus signal should look like. Does anyone know?

My options for ebusd are:
EBUSD_OPTS="--scanconfig -d ens:/dev/ttyACM0"

And this is what the log says:

2024-02-04 22:36:54.198 [bus notice] device status: transport opened
2024-02-04 22:36:54.208 [main notice] ebusd 23.3.23.3-5-g47d2a3aa started with broadcast scan on device: /dev/ttyACM0, serial high speed, enhanced
2024-02-04 22:36:55.606 [bus notice] bus started with own address 31/36
2024-02-04 22:36:55.610 [bus notice] device status: reset, supports info

Thanks for any hints!
Lars

[CrazyPingvin]

Actually, the signal is correct. I used a different oscilloscope with calibrated probes:

As you can see, the signal is either approx. 10V (LOW) or approx. 21V (HIGH) according to the ebus standard [Table on page 4, Receiver column].

I also tried a different RaspberryPI installing the .deb file from the source as described here. Previously I did the manual build process.

Since, nothing of this fixed the issues, I turned to the ebus adapter and updated the Firmware to the most recent version 2024-01-06 as described here.

Now for the first time, I paid attention to the configuraton of the adapter. Turns out it's basic settings are WiFi if I remember correctly as opposed to USB which I was trying. So I changed that to USB and attached everything to the ebus port of the heating system.
Now it works.

The manual actually describes it here "briefly", i.e.

The tab “Configuration” allows adjusting all settings for WIFI station and accesss point, Ethernet (when available) and eBUS:

However, as it does not mention what can be configured for ebus, I missed it. Actually, here you can choose whether you want to use WiFi, USB, Ethernet or the Pins.

So now everything looks fine!

version: ebusd 23.3.23.3-5-g47d2a3aa
update check: revision 23.3 available
device: /dev/ttyACM0, serial high speed, enhanced, firmware 1.1[4106].1[4106]
signal: acquired
symbol rate: 24
max symbol rate: 161
min arbitration micros: 11
max arbitration micros: 5624
min symbol latency: 0
max symbol latency: 38
scan: finished
reconnects: 0
masters: 3
messages: 454
conditional: 2
poll: 1
update: 10
address 03: master #11
address 08: slave #11, scanned "MF=Vaillant;ID=BAI00;SW=0113;HW=9602", loaded "vaillant/bai.0010015600.inc" ([PROD='0010015601']), "vaillant/08.bai.csv"
address 10: master #2
address 15: slave #2, scanned "MF=Vaillant;ID=47000;SW=0420;HW=1403", loaded "vaillant/15.470.csv"
address 31: master #8, ebusd
address 36: slave #8, ebusd

Great project - thanks!