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Does anyone have experience connecting a DS18x20 temperature sensor to a Nodo-Shop OT GW board?

This is the accompanying text:
- PIC connections: LEDs and GPIO pins.
- For use with a DS18x20, disconnect jumpers JP1 & JP2. Place the
DS18x20 in the positions marked 3 2 1 and solder a connection to JP3 to connect the
built-in resistor.
What is meant by disconnect JP1 & JP2 (from what)?
And what is meant by connect JP3 to the built-in resistor, which built-in resistor?

See picture:

Thanks in advanced.

If you look closely, you'll see that there's a thin connection between the two pads of JP1 and between the two pads of JP2. Use a sharp knife to cut those two traces. This disconnects LEDs E and F. I advise to use a multimeter to check that the connection is really cut. Alternatively you can check that LEDs E and F no longer light up when you drive the GPIO ports low with the GA=1 and GB=1 commands.

On JP3 there is no such connection. Here you have to put a blob of solder on its two pads so they become electrically connected. This will connect a 4k7 pull up resistor that is available on the PCB (marked R19) between the DQ and VDD line of the temperature sensor.

Thanks for that information.

So I don't have to solder a 4K7 resistor of my own?

Correct. The 4k7 resistor is already provided on the circuit board. All you need to do is to make a connection on JP3 to attach the resistor to the 1-wire bus.