Fundamentos De Sistemas Digitales Thomas L. Floyd -

She looked inside. It was a box of her grandfather's old watchmaking tools. There, nestled among the tweezers and oilers, was a mechanical counter—a beautiful little device of ten interlocking gears. The first gear turned one full rotation, then nudged the next gear one step. Ten rotations of the first moved the second once. Ten of the second moved the third once.

She saw the flip-flop not as an abstract box, but as a tiny, electrical gear. One electrical pulse (a 1) would make it "flip" to the other state. The next pulse would make it "flop" back. But if you linked them in a chain—the output of one feeding the clock of the next—you built a mechanical gear train out of electricity. fundamentos de sistemas digitales thomas l. floyd

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