Hi,

look at the comment inserted below. I hope it will help you.
Imre

On Thu, 24 Jun 1999, Simon Redwood wrote:

> Pleeease HELP !
>
> I am unable to read the information in an 24C02 eeprom, I can successfully
> write to any address, but all reads return a 'FF', irrelevant of the
> information held in them, which I know to be valid data.
>
> How can I set the port up to read instead of write on the data lines esp.
> DATA_0(pin 2)
>
>
> Regards,
> Simon
>
> unsigned char in_byte(void)
> /* fetch byte, most significant bit first */
> {
>     unsigned char i_byte=0x00;
>     int n;
>
>  SetPortReadmode();                    <------------ set bit 5 of control
> port to 1
>  high_SDA();
>
>  for (n=0; n<8; n++) {
>   high_SCL();
// changing the following line

>   i_byte=(i_byte << 1) | (inportb(DATA) & 0x01);
// actually, you should (and want) to read a single bit instead of
// the whole port...

>   low_SCL();
>  }
>
>  SetPortWritemode();                    <------------ set bit 5 of control
> port to 0
>
>  return(i_byte);
> }
>
>