I'm fairly sure that if the w1-gpio overlay hasn't loaded, then /sys/bus/w1 won't exist. So the fact that it is showing up, even though it is empty, implies the overlay is there.You don't need the 0s.system calls in python if you are using the overlay.
At a terminal
sudo dtoverlay w1-gpio gpiopin=4 pullup=0
then see if they are created in /sys/bus/w1/devices/
If so then you have not setup the correct config.sys (as provided above a few posts)
Furthermore, unless things have changed (it's possible), with nothing connected you would frequently see "ghost" devices appearing as "00-xxxxxxxxxxx" due to the lack of a pull-up resistor on GPIO 4. Seeing nothing implies that the external resistor is connected correctly (or the driver has enabled the internal weak pull, which it didn't use to do).
That all points to the devices not being connected properly.
So I misread the pin descriptions above - that would have been a nice, simple fix, but it is pointing to the device or its connection.
Again, unless the driver has changed, which I can't check at the moment.
Statistics: Posted by rpdom — Wed Jul 23, 2025 3:44 pm