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LPT Port ?

Hi.

I need to read bits from my printer port.
I use DLPORTIO.dll to write the bits.

Now i need to read the bits that are active.

Eg if i write: 1001110

Then i want to be able to close my prog, and read the current status of the port, and actually get back the: 1001110

If u use the read button in the demo, it gets back the value in hex, and i need to get it back the other way.

Can anyone help?

Thanks

alanwhincup

If you can get the value back in hex then you can convert the hex value back to its binary form with a function like below:

function HexToBin(Hex : 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
for I := Length(Hex) downto 1 do
Result := BCD[StrToInt('$' + Hex[I])] + Result;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
ShowMessage(HexToBin('4E'));
end;

Cheers,

Alan

Dennis9

ASKER

its 8 bit result i want eg: 10101101

alanwhincup

I've downloaded and had a quick look at the DLPORTIO.dll and assume you are using the following function to interface between your prog and the driver to read an 8 bit result (or a byte):

function DlPortReadPortUchar(Port : LongInt) : Byte; stdcall;

As this returns a byte then you can convert straight from a byte to its binary form with the function IntToBin() which is implemented in the IdGlobal unit.

ASKER CERTIFIED SOLUTION

Dennis9

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Dennis9,
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