Everybody is good! I come from China, very honored to be here to learn from you.
I recently and friends CG20 calculator to study how to add bluetooth function, if successful will have great help to our work.
Now there is a problem need to solve, I need to know about the casio FZ - CG20 calculator USES what kind of hardware, the hardware specifications; For example, power supply voltage, the peripheral interface chip specification, etc. If who knows please tell me, thank you! Wish you happy every day!

You might find the web sites below useful.

http://community.casiocalc.org/index.php

http://www.casio.co.uk/products/calculators/

http://www.casio.co.uk/education/products/graphic-calculators/fx-cg20/

http://support.casio.com/manualfile.php?rgn=5&cid=004002015

Don't forget the most important source:
http://prizm.cemetech.net/index.php?title=Technical_Info

Thank you very much!