Dear newsgroup readers,
I am currently working on a multiplexer design in VHDL. For the time being the design should run on a Xilinx Virtex II FPGA but actually I am not concerned about any target device later on. My question is more general. What I want to do is multiplex four input signals into one output signal, meaning that there are four parallel inputs that should merge into one serial output. Therefore the output must be four times faster than the input, right? I see problems in generating the faster clock out of the master clock of the slower inputs, that means I HAVE TO provide the fast clock for the serial output right away and then transform it back to the slower to handle the input, is that right? What's more I want to multiplex the signals byte-wise. How can that be achieved WITHOUT wasting a great amount of registers? And how to manage the data being transfered between the two clock domains?