Error when reading file from DS18S20 via DS9490R (USB) 1-wire

I’ve installed 1-wire and a lab-board with 1 DS18S20 connected to a DS9490RUSB adapter on a Raspberry Pi 4 with Home Assistant OS 5.10, core-2021.1.5, supervisor-2021.01.7.
The sensor are detected and shows up, but it doesn’t read/display any value from the sensor. The log shows error

Logger: homeassistant.components.onewire.sensor
Source: components/onewire/
Integration: 1-Wire ([documentation](, [issues](
First occurred: January 27, 2021, 9:42:57 PM (3014 occurrences)
Last logged: 10:49:31 PM

Cannot read from sensor /sys/bus/w1/devices/10-0008018492fd/w1_slave: [Errno 2] No such file or directory: '/sys/bus/w1/devices//10-0008018492fd/w1_slave'

I’m not able to find the problem, any tips what I should look at? The double slash looks suspicious, but I don’t know where to verify or change this.

Found out this, in path “/sys/bus/w1/devices/10-0008018492fd/w1_slave” w1_slave are missing.
I don’t know how to fix this, anyone have any pointers or are the onewire integration faulty?

I think I’ve the exact same issue. When pluging the DS9490R in my laptop ubuntu machine, the w1_slave file exists and correctly reports temperature, but when plugged in my RPi4 with Home Assistant OS 5.12 the file is missing. The device correctly appears in /sys/bus/w1/devices and is exposed in the 1-wire integration of home assistant but then reports “unknown” value.
I can’t figure out what’s going on so any help would be appreciated…

I gave up this, now I’m running owserver on a virtual ubuntu (with the DS9490R) and use the 1-wire integration with the host alternative. Works like a charm.

Look at my other post, I think its your problem