For many years I used a FX-85ES which I unlocked back in my student days to have the features of the FX-991ES through a simple PCB mod, it just required bridging between two contacts labelled P4 on the PCB with solder (I think some people even did it using a pencil).
Unfortunately I've lost that calculator, I actually still have another FX-85ES which I would like to unlock - however this one is a version B with a different PCB that is more difficult to modify.
In reference to the images at http://casiocalc.wik...hardware:pcb-es
The one I previously modded looked like the ones under PWB-GY380-1, I think.
The one I'm now left with looks like the ones under 'Different but looks like 002V02'
I understand from internet trawling that the mod can still be done, and it involves uncapping a component to do the mod. However the images associated with these instructions have been lost to the sands of time so I don't know which component I need to uncap or any other details of how to do the mod. Does anybody know if this requires scraping off part of the cap on the main chip to expose the trace coming from it - or is it something else? Any other details appreciated.