Casio FX991EX

[Tugdual]

I finally opened the EX and had a quick look inside. There is already a video linked but this is my personal addition


Also I measured the voltage on the solar cell and it goes well above 3V while the LR44 doesn't exceed 1.5V. Today is a sunny day and I redid the yesterday test without the LR44 and this time it passed. So a simple light bulb is not enough, you will need the real sun beam.
Ultimately I found some interesting connectors that resemble what we could see on former models of Casios that could be hacked for more features.
Look at the open circuit in betweeen P150 and P151. There are others like that. I tried to shortcut them with no effect.


And trony seems to be a chinese company specialised in manufacturing solar cells http://www.trony.com/. The cell seems to be for indoor usage http://www.trony.com/pdf/2013_embedded.pdf.