I have a Photon applications with a CR2032 battery attached to VBAT. When powering the whole thing down while still having the backup battery attached to VBAT, I observe that the status LED is glowing RED at a very low level: you can hardly see but its there and it vanishes as soon as I remove the backupbattery as well.
I know that in one of my earlier experiments with this particular device (an application without a backup battery, btw) I blew up the D0 GPIO as a result of some clumsiness. However the other inputs and outputs seemed to act correctly. So this device seems to work rather normal; the only noticeable thing is the RED glowing when the CR2032 is attached, which still makes me doubt as to whether I should I should use this device or simply throw it away.
@Jan_dM This sounds like a hardware issue rather than a Firmware Libraries?
I can confirm that a ‘normal/undamaged’ Photon does not have its LED glow dimly red when a coin cell battery is connected between VBAT and GND.
You could dispense with the backup battery and connect VBAT to GND - suggest a reading of the Retained RAM Tutorial by Rick to understand this
Otherwise if you need backup through powerdown then use eeprom? This might avoid you throwing away the hardware which is 95% operational. FYI - I have a small collection of Photons which had D3 or D4 fried due to lack of ESD protection - they are still useful for prototyping so long as D3/D4 aren’t used.
Thank you for the quick response.
And of course it is hardwarean instead of firmware libraries; I was too quick in issuing my request, without looking accurately at the categories. I appologize for that.