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Topic: Sparkfun 9 DoF sensor stick problems. (Read 5 times) previous topic - next topic

Fabio Varesano

No, they are not dead. Just disable the pullups (see my guide How to disable internal Arduino ATMEGA pullups on SDA and SCL with I2C bus ) and check that your connections are like these and you should be fine.

Fabio Varesano

Also, it's perfectly fine to connect the power to 5V as that board has an integrated voltage regulator which will take care of lowering it to the 3V3 used by the sensors.

Fabio Varesano

Regarding the pullup enabling in Wire, well.. I had already opened an issue on the issue tracker asking the developers to fix that.. but nobody gave it a s**t ... You may wanna comment there if you think I was right.

Timmmm

Thanks for the replies. Fabio, what makes you think they aren't dead, given that I connected them to the 5V pull-ups and the datasheet for the ADXL345 says SDA and SCL can't go above Vdd (3.3V) plus a tiny bit? And if they aren't dead, then I can't see why my code didn't work with the internal 5V pull-ups disabled (it seems the schematic shows 3.3V pull-ups built into the sensor board).

Timmmm

Also, I hooked it up to an oscilloscope. It seems like the address is sent, but the ACK bit isn't set by the ADXL345. Also note that it is 3.3V (vertical division is 2V).


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