When i started with the project i hooked it up to the OSC out from the Microcontroller and i fet that line directly to the clocksource of the smartcard.
It then worked.
But now when i maked the project a bit bigger (i use now a UTP cable for the power source)
i looks like there some kind of noise on the microcontroller now it
resets some times (only when i put in the card) .....
how could i hookup a crystal to use it as a clock input.
i already tried use of a NPN transistor but it didn't worked.
(with a 1Mohm res on the base pin)
the RS232 data what i then recieve is a big mess...(from both pics)
any one an ideas?
what happen when i put 2 crystals on the first microcontroller circuit..??
what do you need help with?
you mention card reader, transistor and osc output of the microncontroller? and the card reader needs external clock?
so what make, what model, what mcu, what connection...
what is the lenght of the UTP cable and how is it connected (only one pair,
or two pairs for noise cancelation)