Posts made by Omega303

@Nathan-Bertram Although I found a DS18B20 spec telling the sensor can be driven from 3.0 to 5.5 Volts, I recommend the 3.3 V instead of 5V. But more important is to insert a 4.7 kOhm resistor between data pin and GPIO. I think the missing resistor disables proper communication. The sensor id needs to remain the same - it is the hardware address for the 1-wire master to request data. Here is how I connected the sensor:

@Nathan-Bertram If the 1-Wire interface is set up and a device connected you can read by

 cat /sys/devices/w1_bus_master1/28-01234567890a/w1_slave

where 28-01234567890a is the sensor id. This file only exists if all modules loaded correctly and an device is connected.

SUCCESS Thanks @Lazar-Demin - for getting the packages for 1-Wire interface into the Omega firmware. 21.875°C is the first temperature I read from a DS18B20 via Onion Omega. I am putting together a tutorial to document the steps needed to get the 1-Wire interface up and running. What is your preferred format? Is markdown sufficient?

@Nathan-Bertram : You need the kmod-w1-gpio-custom to tell the 1-Wire interface to which GPIO pin you connect your data wire. Thats done by creating a file at

• /etc/modules.d/55-w1-gpio-custom

containing only one line:

  w1-gpio-custom bus0=0,19,0

where 19 is GPIO pin (replace that number by the pin your sensor is connect to)

Really great, thanks @Lazar-Demin the upgrade went well
The 1-wire interface seems to be initialized on the onion. But - shame on me - I missed the actual driver for the thermal sensors. The driver is included in kmod-w1-slave-therm
Could you add this package possibly?

Thanks so much @Lazar-Demin for looking into it. I really appreciate your efforts.

Looks good - a friend of mine got the 1-wire interface up and running with the onion omega. But he had to compile the firmware all from scratch.

I would rather like to stick with the original distro. But a dependency issue keeps me from installing the required package kmod-w1-gpio-custom

opkg -A depends kmod-w1-gpio-custom

kmod-w1-gpio-custom depends on:
kernel (= 3.18.20-1-7bed08fa9c06eb8089e82c200340ec66)
kmod-w1
kmod-w1-master-gpio

But checking the kernel

opkg info kernel

• Package: kernel
• Version: 3.18.23-1-65008811ac4622ed020e0bf6384ece5a

tells that the package requires an older kernel or the package dependencies need to be adjusted. Does anyone know how to get the package kmod-w1-gpio-custom installed?

Yes thanks @Kit-Bishop - opkg update revealed the w1-packages. And kmod-w1-gpio-custom looks promising. Unfortunatelly the dependencies can not be satisfied, since w1 packages require kernel 3.18.20 but the Omega already has kernel 3.18.23 after the update. Where can I adjust the dependencies? (The option --force-depends did not work and led to further issues.)

Thanks @Kit-Bishop , I would love to use OWFS. But there seem to be no 1-wire related packages. opkg list returns nothing with 1-wire. (Omega Firmware 0.0.6 (b266))

Shoud I expect this packages in the default firmware? Or can I add some missing packages via opkg install <package>

What would be the correct package names? And which GPIO pin would be the data wire?

I would like to connect temperature sensors DS18B20 to the Onion Omega via 1-Wire interface.

Does anyone know how to setup and configure it?