When working with a circuit that depends on multiple IC's with multiple crystals, do the values of those crystals relate to each other in any way? For instance - I'm working with an Atmega128 microcontroller which also uses an FTDI USB-RS232 chip. Both require crystals to operate. I'm wondering if they have to be the same value? or if each relates independent of the other. My only guess is that if one was significantly faster than the other there may be timing issues in dealing with the transmission of data between each. If that is the case then, I'd like to know what the formula is for determining how fast each must run.
Thanks in advance!
Thanks in advance!