using 1-w Linux Kernel Modules
3076 Views - Created 17/02/2020
recently I bought a 1Wire Pi Plus. I intend to use the board with Raspian Buster. I tried to test the board in combination with a RaspberryPi 4, as this fails, with a 3B+. I2C installation seems to work on booth Pis, device is detected 0x18. I intend to use the Kernel Modules. With the 1-wire interface enabeled - /boot/config.txt -dtoverlay=w1-gpio, I find a w1 directory in "/sys/bus" with faulty files. When I comment out - #dtoverlay=w1-gpio - and insert instead - dtoverlay=ds2482 - I do not find a w1 folder in "/sys/bus". This is also true when adding w1-therm to config.txt. Installation of OWFS failed, some errors during installation. I'm reluctant to use OWFS at all, as I do not know, whether the package works under Python 3, I use only, and as there are many issues reported. Tutorial are old, outdated probably. What's to do, to get a running system?
The ds2482 overlay does not appear to work on Raspbian Buster so you will have to enable the kernel module manually. The following steps should work.
sudo nano /etc/modules
Add the following to the end of the file:
Save the file and then edit /etc/rc.local
sudo nano /etc/rc.local
Add the following after the comments but before the exit 0 line:
echo ds2482 0x18 > /sys/bus/i2c/devices/i2c-1/new_device
Save the file and reboot.
Your 1-wire devices should now be available in /sys/bus/w1/devices
Make sure you remove dtoverlay=ds2482 and dtoverlay=w1-gpio from /boot/config.txt otherwise it may not work correctly. I tried the steps above with a Raspberry Pi 4 and a clean install of the latest Raspbian Linux and the two devices on my 1 Wire Pi Plus appear in the devices folder.
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