08-21-2013, 01:03 PM
(This post was last modified: 08-21-2013, 01:12 PM by properinglish.)
I was just looking through the forums and saw this - just wanted to say it made me smile. 
Nice work cut!
ps. I made a more compact 1 tick XOR a few months back - I will build it on the server for anyone who's interested.
Edit: And newo, to add to what Cut said - it uses NOR to control carry propagation so that the first half adder is effectively one tick. It also takes advantage of a trick that Darkroom came up with that allows NAND to be used so that the third layer is 1 tick. The result in an 8 bit PLA is 1 tick for the half adder, 1 tick for the first two layers of lookahead, 1 tick for the third layer of lookahead, and 1 tick for the XOR on the end.
Nice work cut!ps. I made a more compact 1 tick XOR a few months back - I will build it on the server for anyone who's interested.
Edit: And newo, to add to what Cut said - it uses NOR to control carry propagation so that the first half adder is effectively one tick. It also takes advantage of a trick that Darkroom came up with that allows NAND to be used so that the third layer is 1 tick. The result in an 8 bit PLA is 1 tick for the half adder, 1 tick for the first two layers of lookahead, 1 tick for the third layer of lookahead, and 1 tick for the XOR on the end.