It appears that the latest shipment of Photons has issues with I2C. I am using the SparkFun Photon Wether Shield and can not get valid data from the humidity, temperature or pressure sensors. Apparently, Core does work properly with the SparkFun Weather Shield but not with Photon.

@wmjenk , the latest 0.4.3rc2 release of the system firmware fixes these issues. If you want to flash this version onto your Photon, look here . :grinning:

I was having problems with the BMP085 example - all sorted now with the new firmware revision. Thanks !

Thanks for the suggestion. I did successfully flash my new Photon with 0.4.3rc2 of the firmware. I reloaded the SparkFun Photon Weather Shield basic example (temperature, humidity,pressure, altitude readout) and I am still getting bogus data: Temp:31.10F, Humidity: 998.00%, Pressure:-999.00PA, Altit…

I double checked the OTA update and made sure I updated both part 1 and part 2. I then re-ran the SparkFun basic example. It provided the following serial output: Temp:83.01, Humidity:47.94,Pressure:452.00Pa, Altitude:370.94ft Temp:31.01F, Humidity:998.00%, Pressure:-999.00Pa, Altitude:-3277.56ft. …

@wmjenk , I have a Sparkfun weather shield and I’ll be looking at this issue this weekend :smile:

Great, thanks. Joel Bartlett (author of the weather shield setup guide) at Sparkfun replicated the issue on Photon but the code works fine on Core. He thinks it is a firmware issue.

@wmjenk , just realized that the sparkfun shield I have defaults to using the onboard regulator and an external power supply. This explains why the I2C stuff doesn’t work - NO POWER when I use the Core/Photon USB!!! I will fix the jumper and report back.

@wmjenk , yup that was the problem as least with the Core. I will be testing the Photon later (after I go see Ant Man!).

Enjoy Ant Man! BTW, I have my Photon powered from the Photon USB not an external supply

@peekay123 , any luck replicating the I2C issue with a Photon and the SparkFun Photon Weather Shield?

Photon I2C bus issues

Troubleshooting

mdma August 17, 2015, 8:33pm 19

A new release candidate is available for download that fixes these issues. Particle Firmware Updates Thread

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Photon I2C bus issues

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