I am working on a project where I am interfacing a Atmel 89c52 to a SLE4428 card from Schlumberger.

I am able to read the card perfectly, but unable to do a PSC verification or writing to the card. I have only one datasheet for the card which we downloaded from the net ( 4/94 ).

I have never had a problem with I2C interfacing, with multiple E2PROMS, etc., but this card is baffling me ?

Can I get some help ? Is there something which is to be done, but not mentioned on the datasheet, which I am missing ?

Thanks in advance

Leena.