The fetch unit at the head of the pipeline started of with very little functionality, my additions today expand that to deal with situations where the fetch unit does not fetch and dispatch an instruction.
In this video I use the 74LS541 driver to control instruction fetching and use a one gate from a 74LS32 quad OR to control the program counter increment.
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https://www.youtube.com/watch?v=SpdK6cvBoAU