There is a bit in the control register that controls the direction of the
data lines in ECP and PS2 modes. If bit 5 of the control register (base
address + 2) is set to 1, the data lines are inputs. If it is set to 0, the
data lines are outputs.

Here's some code to set it:

BYTE byControlReg = 0;
WORD wBaseAddress = 0x378; // or whatever

//
// Set the direction bit in the control register to read
//
byControlReg = _inp( wBaseAddress + 2 );
byControlReg |= 0x20;
_outp( wBaseAddress + 2, byControlReg );

//
// Now you can read from the port....
//

At 02:16 PM 6/26/98 PDT, you wrote:
>Hi all,
>
>I am working on an X.25 analiser using a 16C73 but the serial port on
>most PC's are too slow for the rate I need to tranfeer data to my PC.  I
>am currently working on a paralell interface on an ECP port.  I need to
>set the data direction registers to all inputs on my pc but don't know
>how.  I have compiled some code to read them but it doesn't work yet
>because they are set to outputs.  If Anybody out there has any ideas (in
>'C') I would be very thankfull.
>
>Here is my code so far:)
>
>#define data    0x0378                   /* LPT port address */
>
>
>void    main (void)
>{
>        int     in;
>        while   (1)
>        {
>                in = inport (data);       /* read the data port */
>                printf ("The data on the port is %i \n",in);
>        }
>}
>
>
>Thanks in advance,
>Brian.
>
>