Anand_kumar:
Yeah I'm using digitalRead() and it will have ~4us delay(based on the tests that I ran with the code) but I'm searching for other ways to read the digital data which is much faster or more precise than the present one.
Well I have have already suggested 2 better alternatives.
My application is to read serial data coming out of an RFID based hardware working at 125kHz.
Why didn't you say so at the start and post a link to the datasheet for the RFID device. I suspect none of this exploration would have been necessary.
...R