Ouch! Problem 5b

Ooops! It looks like I must have disengaged my brain before I wrote this email. It turns out you do need to be able to add extra inputs to the box, where each such input is a constant (that is, always 0 or always 1). BUT, again, no additional logic gates, just the two 2-to-1 muxes. Sorry. Good luck! Yale Patt On Fri, Sep 22, 2017 at 09:17:28PM -0500, Yale N. Patt wrote: > It seems like I can not walk from one point to another on the campus without > one of my 306 students stopping me with another creative mechanism to add to > the statement of Problem 5B. I do admire the creativity to try to get around > the difficulty of the problem, but the challenge is to solve the problem > (which I admit is very tricky and only there to provide a challenge for those > who like challenges) as stated. > > Let me try one more time to make it clear. > > 1. Draw a box. > 2. Label two inputs to the box A and B. > 3. Label the output of the box F > > You have two 2-to-1 muxes to use as you see fit. Each mux has four > terminals: three inputs (source 1, source 2, select line) and one output > (the output of the mux). > > Your job: Put the two muxes in the box and make whatever connections you need > to so that the output F = A XOR B. Connections are to inputs A,B, to the > output F, and to the four terminals of each of the muxes. > > You are not allowed to add NOT gates, you are not allowed to add additional > input 0's or input 1's. You are not allowed to anything other than wires > to make the connections you need inside the box. > > To stop the obsessing about 5B, we will not deduct any points from your > problem set if you do not solve problem 5B. > > Have fun! > > Yale Patt >