to use a lever you whould have to split the signal in to 3, then delay 2 of them, one more than the other. the 2 delayed splits whould go in to an xor so that the output of the xor is true from the least delayed plit hits it until the most delayed plit hit it making it in to a pulse, then split this output in 2 again in to 2 seperate ANDgates the not delayed split whould then have to be split yet again, one of these splits whould have to have a NOT on it, an these 2 splits go in to the other 2 inputs of the 2 ands. then have 1 and go to the bottom and the other to the top