Re: A83: _getkey calls

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Re: A83: _getkey calls


>If I use the following snippet:
>
>Getkey:
>            call _getkey
>
>Will a keypress that is a numberic integer (0-9) register AS 0-9, or will it
>be the hex code for those keys?
>I am really hoping for just ints...but somehow I doubt it.
>Wes

This is how you use _getkey:

Reading Keypresses on the TI-83


There are two ways to read keypresses on the TI-83.

1) Poll for keypresses using a software loop that is waiting for
   a keypress. To do this use the ASM routine "_getky".
   This is exactly the same functionality that is available
   in the TI-83 programming language instruction "getKey".

;---------------------------------------------------------------
; _GetKy - get row/column code of the last key pressed on the keyboard.
;
;		Row/column code is a two- or three-digit decimal
;		code for the last key pressed on the keyboard.
;               The first one or two digits is a number from 1 to 10
;		indicating the row number, the last digit is a
;		number from 1 to 6 indicating the column number
;		of the key.  Code 0 means no key has been pressed
;               since the last call to _GetKy.  The [ON] key does
;		not have a row/column code.
;
;              output:  OP2 := row/column code ( fp value)
;                       refer to the TI-83 manual for "getKey"
;                       key code diagram.
;---------------------------------------------------------------


           A major disadvantage of using this method is that the TI-83 
will
           execute at full speed and waste battery life.

           This method should be used only if you need to infrequently
           look for a keypress.

2) Use the TI-83 system keypress routine. This routine will
   enter low power mode and wait for a keypress or for APD time to
   expire. This routine's output is also different; it returns
   actual keypresses and not key locations on the keyboard. This
   routine will return different key codes if 2nd or alpha is
   pending.

   Since handling an APD condition is not a trivial task without
   documentation available, set this flag using this routine :

      runindiconly,(iy+indicflags)

   This allows the run indicator to run, but APD does not.
;---------------------------------------------------------------
; _getkey - get a keyboard token.  Halt until one becomes (low power)
;	   available.  Automatic power-down counter is turned on
;	   until a valid key has been received.
;	   This routine also handles:
;		1.  [2nd] and [Alpha] shift keys.
;		2.  Contrast settings.
;
;              output:  a = key or 00 if ON key was pressed.
;---------------------------------------------------------------

note : some 2nd and alpha functions are treated the same as
       1st functions ont the TI-83.

        ex : left arrow & alpha left arrow are treated as just
             left arrow by the TI-83 system, but seperate
             keycode is returned for each. The tables below
             show the TI-83 usage of the keypress, you can interpret
             1st, 2nd, and alpha presses however you choose.

The key codes are available from:

http://www.ti.com/calc/docs/83asmkey.htm

From,
     Wesley Moore

______________________________
Email: moore.w@patash.com.au