firemonkey android crc16 result mismatch with delphi for windows

  

in two different project i need to use crc16 checksum.one in windows and other in android.i used a code for windows and it worked prefect.

showmessage( bin2crc16(HexToBin(‘1234′)) ); //—> 0EC9

here is used function for winsows

function Pow(i, k: Integer): Integer;
var
j, Count: Integer;
begin
if k>0 then j:=2
else j:=1;
for Count:=1 to k-1 do
j:=j*2;
Result:=j;
end;

function BinToDec(Str: string): Integer;
var
Len, Res, i: Integer;
Error: Boolean;
begin
Error:=False;
Len:=Length(Str);
Res:=0;
for i:=1 to Len do
if (Str[i]=’0′)or(Str[i]=’1’) then
Res:=Res+Pow(2, Len-i)*StrToInt(Str[i])
else
begin
//MessageDlg(‘It is not a binary number’, mtInformation, [mbOK], 0);
Error:=True;
Break;
end;
if Error=True then Result:=0
else Result:=Res;
end;
//——————————————————————————
function CRC16CCITT(bytes: array of Byte): Word;
const
polynomial = $1021;
var
crc: Word;
I, J: Integer;
b: Byte;
bit, c15: Boolean;
begin
crc := $FFFF;
for I := 0 to High(bytes) do
begin
b := bytes[I];
for J := 0 to 7 do
begin
bit := (((b shr (7-J)) and 1) = 1);
c15 := (((crc shr 15) and 1) = 1);
crc := crc shl 1;
if ((c15 xor bit) <> false) then crc := crc xor polynomial;
end;
end;
Result := crc and $ffff;
end;
//——————————————————————————
function HexToDec(const Str: string): Integer;
begin
if (Str <> ”) and ((Str[1] = ‘-‘) or (Str[1] = ‘+’)) then
Result := StrToInt(Str[1] + ‘$’ + Copy(Str, 2, MaxInt))
else
Result := StrToInt(‘$’ + Str);
end;
//——————————————————————————
function bin2crc16(str: string): string;
var
I:integer;
lengthCount : integer;
crcByteArr : array of Byte;
crcOut : Word;
begin
lengthCount := Trunc(length(str)/8);
setlength(crcByteArr , lengthCount );
for I := 0 to lengthCount-1 do
begin
crcByteArr[I] := BinToDec(copy(str, I*8+1, 8));
end;
crcOut := CRC16CCITT(crcByteArr);

result := crcOut.ToHexString;

end;
//——————————————————————————
function HexToBin(Hexadecimal: string): string;
const
BCD: array [0..15] of string =
(‘0000’, ‘0001’, ‘0010’, ‘0011’, ‘0100’, ‘0101’, ‘0110’, ‘0111’,
‘1000’, ‘1001’, ‘1010’, ‘1011’, ‘1100’, ‘1101’, ‘1110’, ‘1111’);
var
i: integer;
begin
Result := ”;
for i := Length(Hexadecimal) downto 1 do
Result := BCD[StrToInt(‘$’ + Hexadecimal[i])] + Result;
end;

but for android i changed the code to handle zero index string.
the result is different

memo2.Lines.Add( bin2crc16(HexToBin(‘1234′)) ); //—–> 1AFa

here is used functions in android

function BinToDec(Str: string): Integer;
var
Len, Res, i: Integer;
Error: Boolean;
begin
Error:=False;
Len:=Length(Str);
Res:=0;
for i:=0 to Len-1 do
if (Str[i]=’0′)or(Str[i]=’1’) then
Res:=Res+Pow(2, Len-i)*StrToInt(Str[i])
else
begin
Error:=True;
Break;
end;
if Error=True then Result:=0
else Result:=Res;
end;
//——————————————————————————
function CRC16CCITT(bytes: array of Byte): Word;
const
polynomial = $1021;
var
crc: Word;
I, J: Integer;
b: Byte;
bit, c15: Boolean;
begin
crc := $FFFF;
for I := 0 to High(bytes) do
begin
b := bytes[I];
for J := 0 to 7 do
begin
bit := (((b shr (7-J)) and 1) = 1);
c15 := (((crc shr 15) and 1) = 1);
crc := crc shl 1;
if ((c15 xor bit) <> false) then crc := crc xor polynomial;
end;
end;
Result := crc and $ffff;
end;
//——————————————————————————
function bin2crc16(str: string): string;
var
I:integer;
lengthCount : integer;
crcByteArr : array of Byte;
crcOut : Word;
begin
lengthCount := Trunc(length(str)/8);
setlength(crcByteArr , lengthCount );
for I := 0 to lengthCount-1 do
begin
crcByteArr[I] := BinToDec(copy(str, I*8, 8));
end;
crcOut := CRC16CCITT(crcByteArr);

result := crcOut.ToHexString;

end;
//———————————————————————————–
function HexToBin(Hexadecimal: string): string;
const
BCD: array [0..15] of string =
(‘0000’, ‘0001’, ‘0010’, ‘0011’, ‘0100’, ‘0101’, ‘0110’, ‘0111’,
‘1000’, ‘1001’, ‘1010’, ‘1011’, ‘1100’, ‘1101’, ‘1110’, ‘1111’);
var
i: integer;
begin
Result := ”;
for i := Length(Hexadecimal)-1 downto 0 do
Result := BCD[StrToInt(‘$’ + Hexadecimal[i])] + Result;
end;
//———————————————————————————
function Pow(i, k: Integer): Integer;
var
j, Count: Integer;
begin
if k>0 then j:=2
else j:=1;
for Count:=1 to k-1 do
j:=j*2;
Result:=j;
end;

how can i fix my problem !?

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