Electron I2C Bus

I am able to see my I2C pressure sensor with my Photon. However, when I switch over to my Electron it is not producing the same output. I was wondering if there is something I’ve missed? I’ve tried using the following pairs D0/D1, D1,D2, and C5, D0. I’m using the same pull-up resistors as I did with the Photon. I’m really not sure what I’ve missed.

Thank you!

Be sure you did not use the wrong pins. :smiley:

D0/D1 matches the same pins on a Photon so you can take reference from there just to be sure.

I’m positive I have used the correct pins.

I2C seems to be working fine for my electron. I did a test with a BMP085

Pressure Sensor Test

Sensor:       BMP085
Driver Ver:   1
Unique ID:    10085
Max Value:    300.00 hPa
Min Value:    1100.00 hPa
Resolution:   0.01 hPa

Pressure:    1007.07 hPa
Temperature: 31.60 C
Altitude:    51.58 m

I’m not sure what was going on, but it seems to working today. Pretty odd though. Thank you for the help!

I found out my problem. I was using two different references with varying labels for SCL and SDA.

The marking in that pdf is incorrect. How do I go about alerting someone at Particle about this issue?

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sorry for the confusion. I have pinged the engineer who made the diagram and filed an issue here: https://github.com/spark/docs/issues/310

I have, for now, removed the pin-out diagram to prevent any confusion!

Thanks for letting us know :smiley:

Thank you for all the help! It makes complete sense why my circuit wasn’t working as I expected. I was using both the firmware guide and the pdf as references.

In the future, whats the best way about reporting an issue? Filling out an issue on Github? Or posting on the forum? Thanks in advance, I’m still new here.

Opening an issue on github would work fine too. Mainly to file a bug i guess? There’s more people in the community who can help with issues and try to resolve faster.

Such issues with bad references should not happen and needs to be fixed asap. :smiley:

Just to update, I looked over the PDF and it’s correct… just needs clarification because of where the labels are… it’s hard to know which pin they belong to. See my post here with suggested update to pinout: https://github.com/spark/docs/issues/310 Does that work for everyone?


@BDub that’s a great suggestion :smile:

@BDub, your suggestion will make it more clear to use that reference diagram in the future. Thank you!