
Dumb thermometer gets digital output - SauliusLukse
http://kurokesu.com/main/2017/02/20/dumb-thermometer-gets-digital-output/
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moftz
That's a neat way to do it without opening the device but it might be easier
just to crack it open, find the chip and look for communications to either the
LCD or even better, an LCD driver chip. Translate using an arduino whatever
communication, either SPI or straight GPIO, coming from the main chip into
whatever you need. This OCR looks fast to prototype but it's added computing
resources and added cost (a webcam versus a $1 chip).

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nemik
His way is a lot safer. It's never a "$1" chip, you also need a power supply
for that chip, breadboard (or dev kit) which puts price into cheapo webcam
range.

On top of that, breaking out to LCD pins or their drivers is not easy. They're
often very fine-pitch pins, if they have pins at all, some can be QFNP
packages making it even harder to get to the pins. There's a big risk of just
straight-up breaking the thermometer doing this, so if you attempt it, it's
best to buy a backup.

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mikejmoffitt
A lot of these small LCDs interface with a zebra pad, hitting contacts on the
LCD glass and some gold or carbon-coated conductors on the PCB. Gold
conductors are easy, carbon-coated conductors are okay but can be annoying,
but the pitch generally narrow for these, as you've mentioned.

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dTal
Heh. I thought this was gonna be an ordinary mercury thermometer and a webcam
+ computer vision.

Still cool.

