I am trying to get a Omron D6T (http://media.digikey.com/pdf/Data%20Sheets/Omron%20PDFs/D6T44L_8L_Appl_Note.pdf) sensor to talk to my Pi (and vice versa) and thought it would not be a big problem as I have another thermal sensor running over I2C (as of now, the D6T is on the bus exclusively). The intitial steps worked fine, and my sensor appears with its standard address (0x0a) when calling
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i2detect -y 1
I then went one step back and tried to send a packet from shell using
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i2cset -y 1 0x0a 0x00 0x4c
Which is stitched together from various sources of the net, to my belief, "-y 1" refers to /dev/i2c-1, where my sensor is connected, and where it also shows up (see above). Then I specify the sensor address on the bus (0x0a, this is the "unshifted" address), a target register (I really only guess zero here, as I can not recall reading about a specific register to write to) and the command, that I want to send (0x4c) to receive the readings back. Correct me if I'm wrong here.
So, in the end, if I try that, I get "Error: Write failed" again. I know, similar errors are covered all over the net, including here, but so far nothing really applied to my situation. After all, the sensor is listed in i2cdetect and I do only want to write one byte (0x4c), differing from the problem descriptions that I found.
So, my first ideas as to what I should do or think about:
The sensor has some very strange connector that I can not get my hands on in germany in the next few days with affordable effort (3$ worth connectors plus 18$ shipping is kind of the best offer) - so i just soldered my four wires to the pads of the connector, beeped everything through (no obvious shorts! Around 1kOhm between SCL/SDA and Ground, if I remember correctly) and connected it to the Pi. I guess that if the sensor shows up in i2cdetect and does not show up when not connected means that I broke nothing, right?
I was using the sensor powered with 5V from the GPIO pins and using the signal level of 3.3V - no problem with the other thermal sensor (TPA81), which is still working, and of course without any pull-ups to 5V. As I see a problem in that signal level, I included a Sparkfun converter (the two Tx parts) - the detection still works, the writing still doesn't. Will I need pull-ups to 5V on the sensor side now? I am not sure of that.
And this is where my wisdom is through - If anything of the above is obviously false, please let me know. If you have any additional ideas as to what to do, please tell me, too Should you have the same sensor and some code to read from it that works for you, please feel free to post it here