Hi,
I'm trying to communicate with a smart card via iso7816 by emulating the T=0 protocol using a generic MCU's UART interface. One problem I'm having is providing a clock to the smart card(~3.5712MHz) w/o the use of a seperate crystal. Obviously using the GPIO pins would be too slow, and the UART channel doesn't have a SCLK out. It's also impossible to get a divisor for the MCU's clock since the UART prescalar(powers of 2) isn't the same as the smart card's one(372), so they'll never agree on the baudrate if I were to use the MCU's clock. Is there any other way to supply the clock other than use a separate crystal?