CGlocker is an add-in for the Casio Prizm (both fx-CG10 and fx-CG20, of course) which main goal is to provide a way to secure your calculator with a password. The idea is that you open the add-in, set a lock code, and the calculator is locked - only allowing you to turn it off or to input the unlock code (so you can exit the add-in and have access to all the Prizm functions).

This add-in asks you for a numeric unlock code the first time it is run, and then it locks after you press EXE. It saves the code, so the next times you lock the calc, it doesn't ask you for a new code again. To set a new code, press OPTN and then F4.
Press ALPHA to unlock the Prizm when it is locked (it says this nowhere, I'm a bit of a fan of security through obscurity). It will ask you for the code you set before (to validate, press EXE).

List of implemented (I), planned (P) and long-term planned (LP) features:
- 4-digit lock password (I)
- Only unlock with correct code (I)
- Ask for unlock code before locking (I)
- Allow to turn off the calculator when it is locked (I)
- Automatically turn off after locking (I - optional)
- NOT showing Casio logo and owner information while powering off (I - optional)
- Jumping straight to Run-Matrix after unlocking (I - still in testing)
- Store the password in memory so you don't have to set it every time before locking (I)
- About screen with credits (I)
- Store the saved password as a MD5 hash (so it isn't saved as plaintext) (LP)

Download the version 1.0 here:
http://www.cemetech.net/programs/index.php?mode=file&id=723
Or if you prefer to download from a server not related to Cemetech:
http://helium.gbl08ma.com/dl/casioprizm/CGlock.zip

This add-in is licensed under the GNU GPL v2 - the source is included in the ZIP file. Much of this work is possible thanks to the help of KermM, Ashbad, AHelper and probably some more Cemetechians I forgot to refer. The icons inside the add-in are from the Iconic icon set ( http://somerandomdude.com/work/iconic/ ).

Ummm... I don't want to bother people with this, but others' option is really important as it tells me if there's anything that should be corrected or added. I know this is an unfinished add-in and my skills are not that good, but still and because of that, it'd be better if I fix any bug or plan any feature while this is still in an early development stage.

Would this get more attention if it was posted on the Your Projects section?

I can try it out tonight I just turned out to be busier than expected yesterday when I said I would try it.

Today I tested the application...not bad for a alfa indev app


It would be great if you were able to do something like this
http://www.top-progcasio.com/programme-216.html

My suggestions:
in order to define the password, we must repeat it once to confirm the pass

I think the password should always be the same ... and not have to set the pass each time block the calculator ... Of course then there should be an option to change the password (in app settings)

when we insert more than x times the incorrect password, we will be blocked to put password for x minutes (X -
this value should be customizable in the settings of the application)

add the possibility of Shutdown the calculator, and when we turn it on, she asks for a password

...

All of that is planned. As for the last one, I'm still waiting for someone to help me on how to programatically turn off the calc...

Thanks everyone for the feedback... but I still don't know how to allow the calculator to be turned off while blocking Menu...

why block menu? why not do it like fx-lock?

The function for setting up the add-in exit handler has not yet been exposed on the Prizm.

Ideally, I'd like to setup two lock modes: one like fx-lock (allows to see the menu but doesn't enter into any menu item), and another that really blocks everything and just says "calculator locked" (like what it now).

Nice. So do you know how to allow turning off the calculator at all? Even with menu blocked?

If I block Menu, it blocks Shift+AC/ON too. What I want to to either have that handled by my code ("if Shift and AC/ON are pressed, then turn off calc", like I do for unlocking with "if Alpha is pressed, then go to unlock code screen") or to have a GetKey input that blocks Menu but doesn't block the turn off key combo.

Cant you do:

If <menu is pressed>
then <do nothing>
end

And I know, thats lua, not C, but I think its understandable code

That's what I'm doing. (if I weren't using a menu-blocking GetKey, it would go to the menu anyway, but since I am, it does nothing when Menu is pressed).

what is the problem then? is it in a continuous loop? Is that why it wont turn off?

The system function that blocks Menu from following the usual procedure of showing the Menu also blocks the usual procedure of turning off.

by other words, the GetKey function other people use is a "assisted GetKey": it takes care of certain things like Shift+AC/ON, Menu and Shift+7 on its own (you need not to develop code for it, and you can't control what these keys do).
Because I need to lock the keyboard, I must use the GetKey function in a different way: the "expert way", where it does nothing other than return the key pressed to the program (it doesn't care if Menu or Shift+AC/ON is pressed, it just tells the program they have been pressed and then it's your turn).

ah. so there is no way to only block menu and not the other 2?

At the moment, yes; but I'd like to know if there was, that's why I asked

Oh, ok

Doesn't the prizm already have a password prompt at start-up, though?
on the second page of Settings, there's a Username 'manager'
there, you can set a password(i think)

You set a password so that others cannot change your information like your Name and Company, shown on shutdown.

ah... ok. So I found a password, but the wrong type