Unit Bits;

{***************************************************************************}

{* Bit 0 is the LSB, Bit 7 is the MSB

{***************************************************************************}



interface

{***************************************************************************}

{***************************************************************************}

Function  DeciVal(BitNum: byte): byte;

Function  Flip(InByte: byte; BitNum: byte): byte;

Function  IsHigh(InByte: byte; BitNum: byte): boolean;

Function  SetLow(InByte: byte; BitNum: byte): byte;

Function  SetHigh(InByte: byte; BitNum: byte): byte;



implementation

{***************************************************************************}

{***************************************************************************}



Function  DeciVal(BitNum: byte): byte;

{***************************************************************************}

begin

  case BitNum of

    0:  DeciVal := 1;

    1:  DeciVal := 2;

    2:  DeciVal := 4;

    3:  DeciVal := 8;

    4:  DeciVal := 16;

    5:  DeciVal := 32;

    6:  DeciVal := 64;

    7:  DeciVal := 128;

    else

      write(#7);

  end;

end;



Function  Flip(InByte: byte; BitNum: byte): byte;

{***************************************************************************}

var

  BitVal: byte;

  Temp: byte;

begin

  BitVal := DeciVal(BitNum);

  if BitVal and InByte = BitVal then

    Temp := SetLow(InByte, BitNum)

  else

    Temp := SetHigh(InByte, BitNum);

  Flip := Temp;

end;



Function  IsHigh(InByte: byte; BitNum: byte): boolean;

{***************************************************************************}

var

  Temp: boolean;

begin

  Temp := InByte and DeciVal(BitNum) = DeciVal(BitNum);

  IsHigh := Temp;

end;



Function  SetLow(InByte: byte; BitNum: byte): byte;

{***************************************************************************}

var

  BitVal: integer;

begin

  BitVal := DeciVal(BitNum);

  SetLow := InByte and (255 - BitVal);

end;



Function  SetHigh(InByte: byte; BitNum: byte): byte;

{***************************************************************************}

var

  BitVal: integer;

begin

  BitVal := DeciVal(BitNum);

  SetHigh := InByte or BitVal;

end;



{***************************************************************************}

{***************************************************************************}

{***************************************************************************}

begin

end.