' PicBasic Pro program to display key number on LCD

' Define LOADER_USED to allow use of the boot loader.
' This will not affect normal program operation.
Define    LOADER_USED    1

' Define LCD connections
Define  LCD_DREG        PORTD
Define  LCD_DBIT        4
Define  LCD_RSREG       PORTE
Define  LCD_RSBIT       0
Define  LCD_EREG        PORTE
Define  LCD_EBIT        1

' Define program variables
col     var     byte            ' Keypad column
row     var     byte            ' Keypad row
key     var     byte            ' Key value

         OPTION_REG.7 = 0        ' Enable PORTB pullups

         ADCON1 = 7              ' Make PORTA and PORTE digital
         Low PORTE.2             ' LCD R/W low (write)

         Pause 100               ' Wait for LCD to start

         Lcdout $fe, 1, "Press any key"  ' Display sign on message

loop:   Gosub getkey            ' Get a key from the keypad
         Lcdout $fe, 1, #key     ' Display ASCII key number
         Goto loop               ' Do it forever

' Subroutine to get a key from keypad
getkey:
         Pause 50                ' Debounce

getkeyu:
         ' Wait for all keys up
         PORTB = 0               ' All output pins low
         TRISB = $f0             ' Bottom 4 pins out, top 4 pins in
         If ((PORTB >> 4) != $f) Then getkeyu    ' If any keys down, loop

         Pause 50                ' Debounce

getkeyp:
         ' Wait for keypress
         For col = 0 to 3        ' 4 columns in keypad
                 PORTB = 0       ' All output pins low
                 TRISB = (dcd col) ^ $ff ' Set one column pin to output
                 row = PORTB >> 4        ' Read row
                 If row != $f Then gotkey        ' If any keydown, exit
         Next col

         Goto getkeyp            ' No keys down, go look again

gotkey: ' Change row and column to key number 1 - 16
         key = (col * 4) + (ncd (row ^ $f))
         Return                  ' Subroutine over

         End