Casio Fx-991es Plus Rom

Upgrade Your Casio Fx-82es Into 115es/991es/570es: The circuits of Casio fx-*es series are almost the same, except. NOT MS or ES PLUS series. Turn on your calc, press shift+7+on, press shift until the screen shows ROM 018 MODE P*.

The following list was written by user202729 and serves as the guide to this forum thread... Also available in the Javascript code above.

No longer needed now as we already have the ROM. Hardware description:,. (no English translation this time). High-level functions: * There are some outdated information about 'real address' and 'emulator address'. Now we had the real ROM of the calculator that is not necessary.

Edited by SopaXorzTaker, 28 February 2018 - 02:22 PM. Add user202729's markdown version. Now the little A and B from the Reg menu have a weird behavoir.

They have the same effect as r where it freezes they correspond to 89 and 8A respectively 89 is jump A24, as per Hitachi. 8A is call A16.

This means jumping to address contained in the next two (16) or three (24) bytes. It *may* explain some of the glitches encountered, though I don't know what r and Ans do, as they correspond to undefined instructions. Hm, maybe crafting hackstrings is possible using this method. Let's try: (x(((x(((x(((x(((AnsAns Where x is that X character with a hat. Corresponds to jmp 0x282828 (Hitachi), which might do something. By the way, this shows some weird firmware running on a calculator. Edited by SopaXorzTaker, 22 August 2016 - 05:42 AM.

Now the little A and B from the Reg menu have a weird behavoir. Interesting to know that fx-82 ES plus and fx-991ES plus are SuperH architecture I am a fx-82 ES Plus owner, if you want me to test something in the calc, please, tell me. (Now, I'm in holidays) Can you please take your calculator apart (if you do it carefully, it won't break) by unscrewing the screws on the back and opening the case? If you can, please photograph the circuit board inside. This may help in our research. You can also test the hackstrings which we were discussing above. Edited by SopaXorzTaker, 22 August 2016 - 06:27 AM.

Interestingly, if I try A on the end of that, it shows Maths error as expected. But then if I delete the A and put the X hat character (the one from the Reg menu) and press equals on the same sequence, it actually works but nothing else happens (and nothing seems to glitch). If I press equals again it this time freezes. However with r it always freezes regardless. Maybe we are getting somewhere with the X hat from reg menu Try replacing the Sqrt with another function such as log, ln, etc.