Simulating a clock signal with microprocessor?

Question

I have a microprocessor (ATMega 128) that I am hooking up to a smartcard connector. I've programmed the chip to read/write according to the ISO standard for smartcards... my question is can I simulate a clock for the smart card using the ATMega (ie. using one of the i/o ports and toggling it as needed)?

Answer 1

I'm not sure about your particular implementation, but in my experience, only a crystal will act as a reliable oscillator - I have tried toggling I/O ports as you suggest, but if timing is important in your hardware/controller equipment, I wouldn't recommend it.

christo