Do you know how to reconfigurate the DFS of Spartan DCM at runtime?
I would like to change the FXMULTIPLY AND FXDIVIDE in order to get different CLKFX at runtime. According to xilinx manual it's not possible.
But probabely smbd has just a good idea?
PS: a simple reload of the FPGA configuration is too slow...
Does the Spartan 3 have BUFGMUXes like the Virtex-II Pro? If so, you could it it differently alltogether... Use two DCMs to create the two clocks you want to switch between, and feed them into the two inputs of a BUFGMUX... then you could just chose the desired output clock by changing the select signal.... not sure what happens to attached logic during the switch, though...
cu, Sean
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