Help Needed: Talk to an LM75 chip using I2C via the Extender module

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1

I’m making an attempt at getting my Fez Spider to talk to an LM75 temperature measuring chip via I2C connected to the mainboard via an extender module on socket I.

Link to LM75 Datasheet is: http://datasheets.maximintegrated.com/en/ds/LM75.pdf

I have connected the Extender Module’s pins (the blue labelled pins) according to the schematic attached. The schematic is based on Figure 7 in the datasheet.

Question 1: Can someone validate the schematic and tell me whether I am hooking things up correctly?

Question 2: What is the bare minimum code needed to verify that my Spider can talk to the LM75 chip?

Thank you in advance!

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In my experience an I2C address is only 7 bits. The LSB is the in/out indicator. Try address 0x48 instead of 0x91.

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I2C addresses ARE only 7-bit long. So your address is wrong.

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I am, in fact, using the wrong address. I’ll try my stuff with the correct address and report back.

5

The problem was that I was talking to the wrong address! Thanks for the help, guys!

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awesome, great to hear. Please tick Dave’s response so we know this question has been answered !