Interestingly, this is partially how I realized I wasn't actually that great at programming. I really have just never been very good with digital logic and have failed to really grasp it multiple times. Starting 6 or 7 years ago, attempting to design a 6502 computer, and could not for the life of me, figure out how to design the address decoding how I wanted, and more recently, trying to get into FPGA's. I'm not sure what it is, as at a very broken down, individual level everything makes sense, but as soon as it jumps into composing them into anything (i.e. an address decoder or even just simple digital logic devices) I get lost and have to just sit around and have to drill the details down on paper for me to remotely get it.