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Hi, on a pi3 with kernel 4.9.40-v7+, I am unable to see any 1w device. I have two DS18B20 and one relay (https://store.brewpi.com/temperature-control/solid-state-relays-ssr/brewpi-onewire-ssr-expansion-board). Test made with a single DS18B20 connected directly via RJ12 plug. Solderings of the RJ connecter have been tested ok with ohmmeter.No sensor is seen:owdir/bus.0/uncached/settings/system/statistics/structureHowever the pi seems to communicate with the board:pi@pi3-sdr:~ $ i2cdetect -y 1 0 1 2 3 4 5 6 7 8 9 a b c d e f00: -- -- -- -- -- -- -- -- -- -- -- -- --10: -- -- -- -- -- -- -- -- 18 -- -- -- -- -- -- --20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --70: -- -- -- -- -- -- -- --i2cdump -y 1 0x18No size specified (using byte-data access) 0 1 2 3 4 5 6 7 8 9 a b c d e f 0123456789abcdef00: XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX 08 XXXXXXXXXXXXXXX?10: XX XX XX XX XX XX XX XX XX XX XX XX XX XX 08 XX XXXXXXXXXXXXXX?X20: XX XX XX XX XX XX XX XX XX XX XX XX XX 08 XX XX XXXXXXXXXXXXX?XX30: XX XX XX XX XX XX XX XX XX XX XX XX 08 XX XX XX XXXXXXXXXXXX?XXX40: XX XX XX XX XX XX XX XX XX XX XX 08 XX XX XX XX XXXXXXXXXXX?XXXX50: XX XX XX XX XX XX XX XX XX XX 08 XX XX XX XX XX XXXXXXXXXX?XXXXX60: XX XX XX XX XX XX XX XX XX 08 XX XX XX XX XX XX XXXXXXXXX?XXXXXX70: XX XX XX XX XX XX XX XX e9 XX XX XX XX XX XX XX XXXXXXXX?XXXXXXX80: XX XX XX XX XX XX XX e8 XX XX XX XX XX XX XX XX XXXXXXX?XXXXXXXX90: XX XX XX XX XX XX e9 XX XX XX XX XX XX XX XX XX XXXXXX?XXXXXXXXXa0: XX XX XX XX XX e8 XX XX XX XX XX XX XX XX XX XX XXXXX?XXXXXXXXXXb0: XX XX XX XX e1 XX XX XX XX XX XX XX XX XX XX XX XXXX?XXXXXXXXXXXc0: XX XX XX e8 XX XX XX XX XX XX XX XX XX XX XX XX XXX?XXXXXXXXXXXXd0: XX XX 01 XX XX XX XX XX XX XX XX XX XX XX XX XX XX?XXXXXXXXXXXXXe0: XX 01 XX XX XX XX XX XX XX XX XX XX XX XX XX XX X?XXXXXXXXXXXXXXf0: 18 XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX ?XXXXXXXXXXXXXXX Ideas welcome!

Hi

Have you gone through all of the steps in our OWFS tutorial? There is a python script at the end of the tutorial which will show a list of the devices that are connected to the 1 Wire Pi.

It may be worth trying to connect the DS18B20 to the solder pads instead of the RJ12 just to make sure there isn't a problem with the connector or wiring. We have a tutorial for connecting a DS18S20 https://www.abelectronics.co.uk/kb/article/9/1-wire-with-ds18s20-digital-thermometer which is the same pinout as the DS18B20.

Thanks Andrew. You are right, it was a problem of wiring. I contacted the seller of the DS18B20 (https://store.brewpi.com/featured/triclamp-onewire-temperature-sensor) and asked for a wiring diagram of the sensor, and it turned out the pinout of their RJ plug did not match yours.I fixed the cabling and it is now working great. Thanks for the help!