This is an informative post of an observed failure mode and the remediation that brought my heatermeter back.

While changing parameters via webui my heatermeter wigged out. Solid white backlight display with no text. Reboot showed "No Pit Probe" and then quickliy solid white backlight display with no text.

After searching forum posts here and learning what perhaps to check (spi pins in particular due to display involvement) I decided to force re-flash the AVR before breaking out the soldering iron.

Actually I first re-imaged the micro-sd. To no avail. So then:

I chose the local /lib/firmware version and it flashed to no avail - same symptom.

I did notice this was an apparently "older" version so decided to see if a newer firmware existsed that may have some bugs (?) fixed.

I chose the latest (non release) April and it indicated "Blown Fuses" (which the 2017 /lib/firmware didn't show).

But I also noticed a clear-eeprom hex file.

Interesting. No docs. No word. But - hey - I *was* tweaking my Thermocouple calibration in successive increments. Perhaps I corrupted the ee-prom or data cache?

So I flashed that clear-eeprom hex file.

I then, again, chose the latest (non release) April build and it fully flashed and my heatermeter came back!

So if your heatermeter flakes out, particularly during config changes, do try clearign the eeprom before re-flashing the avr firmware. It may be all you need. And also - when making webui changes - I'm thinking it takes a few more seconds for changes to take effect so don't make changes rapid fire.