In SX Microcontrollers, SX/B Compiler and SX-Key Tool, JonnyMac wrote:

As Been points out there is nothing at all wrong with you code.  If, however, you find yourself pressed for space at some point you can reduce the code used using "fancy stuff with bit masks."  It is not as easy to read as your verbose code, but it does use a lot less space.

Here's the Main section:

[code]Main:
  tmpBtns = GET_BTNS
  IF tmpBtns = %00000000 THEN Main

  FOR idx = 0 TO 5
    mask = 1 << idx                             ' create mask for input
    check = tmpBtns & mask                      ' test the button
    IF check > 0 THEN
      Leds = mask
      CNG_PGM idx                               ' change selected program
      DO
        tmpBtns = GET_BTNS
      LOOP UNTIL tmpBtns = %00000000            ' force release
      GOTO Main
    ENDIF
  NEXT

  GOTO Main[/code]
As you can see, this calls a function called GET_BTNS which handles the input debouncing:

[code]GET_BTNS        FUNC    1, 0, 0[/code]

[code]FUNC GET_BTNS
  gbIdx         VAR     tmpB1
  gbResult      VAR     tmpB2

  gbReseult = %00111111                         ' assume pressed
  FOR gbIdx = 1 TO 25                           ' 25ms debounce
    DELAY_MS 1
    gbResult = gbResult & RB                    ' scan inputs
  NEXT

  RETURN gbResult
  ENDFUNC[/code]
Once you get your project working save a new version and try this to see how you like it.  Even if you don't use it here, masking tricks are handy to have up one's sleeve.

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