ibutton sensors

Hello there

So I’m using an ibutton sensor ds1922L with arduino, using Onewire.h library so far I can get the address of the sensor and I can read the crc as well. But somehow I still can’t read the data from the scratchpad

code of ibutton.txt (1.72 KB)

          ds.write(0x44,1);  // start conversion, with parasite power on at the end

Where in the datasheet did you find the command 0x44 to start a conversion? I cannot find a reference for that.

It is not in the data sheet of the sensor, but it is in the onewire library that it can be used to copy data to scratchpad although I searched in the data sheet and didn’t find anything related to it

DS1922L datasheet.pdf (531 KB)

I guess that's for the more common DS18B20 sensor. Try to change it to "FORCED CONVERSION" and post the results.

sorry I took long to update.
so, I am trying the forced conversion as you suggested but to do so I need to read 020Ch address but I can’t do so with the onewire library

so, I am trying the forced conversion as you suggested but to do so I need to read 020Ch address but I can't do so with the onewire library

You can. You have to copy the data to the scratchpad and read it from there. The datasheet has an example of how to do that.