In older (TTL) times such a small RC delay would have been accomplished usi=
ng a
small RC integrator, f.ex. 50R series and 20pF to ground. To work around
glitches and runtime problems I'd try to implement the XOR using the gates =
in a
single 74HC00 package. Simulation may help here... usually implemented XOR =
gates
are glitch-prone due to the different propagation times through the negated=
 and
straight paths. In this case, that glitchiness can be put to good use after
stretching it a little with a RC delay element, I think.

-- Peter

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