You can't however do it with just a bunch of arbitrary clocks and a multiplexor to switch between them - you must arrange that the transition from one clock to the next has clock high/low times that are valid. With a simple mux, you would get glitches that are shorter than either of the clocks that you are switching between and so the CPU will malfunction.
Looking at how the BBC does it may be instructive.
In general, it's much easier to do it for different divisions of a single high-frequency clock, rather than switching between different independent clocks.
Looking at how the BBC does it may be instructive.
In general, it's much easier to do it for different divisions of a single high-frequency clock, rather than switching between different independent clocks.
Statistics: Posted by arg — Thu Jul 03, 2025 10:25 pm