Strange i2c bus issues with Photon

[jaafar]

this problem is discussed here too:

I2C connection randomly fails on P1 & Photon

After updating my P1 to 0.4.3, I have most things working, including I2C where I’m reading a MCP3421 ADC. However, I’ve run into a small issue with the I2C connection: Sometimes it works, and sometimes it doesn’t work. I have my code setup to read data from the MCP3421 every second, so its well within its sampling rate limit. Sometimes when I power on the P1, the readings work fine. Other times, the connection to the MCP3421 fails until I reset the P1. Other times, it works fine for a f…