A-B = Subtract = A + B' + 1, so Y = B'
S Bi Cin Y
0 0 0 0
0 0 1 0
0 1 0 1
0 1 1 0
1 0 0 1
1 0 1 1
1 1 0 1
1 1 1 0
A note on notation. The apostrophe as a boolean operator is generally limited to a single bit. When you mean a bit-by-bit (or bitwise) inversion of a multi-bit value, we typically use the tilde, so ~B.A-B = Subtract = A + B' + 1, so Y = B'
Don't guess.I'm guessing Y = 1, because we've got B, B' and 0, and because in the partially-completed table I've got, Cin=0 S=1 yields Y = 1.
So that gives me a completed Y column in my truth table:
And K-mapping that gives me a result of Y = S*Bi' + Bi*Cin'Rich (BB code):S Bi Cin Y 0 0 0 0 0 0 1 0 0 1 0 1 0 1 1 0 1 0 0 1 1 0 1 1 1 1 0 1 1 1 1 0
I realize that, which is why I indicated that the 4-bit discussion was by way of example. The only value of n for which your solution is not a coincidence is for n=1.Uh...for the record, the question states that the two inputs, A and B, are n-bit, not 4-bit.
Here you go guessing again. And this time you are wrong. And it comes back to your refusal to do what I asked for at the very beginning, which was to draw the circuit for a multi-bit adder using full adders as your building blocks. But you want to keep just rushing past the stuff you don't understand and it just keeps biting you in the ass down the road.But anyways, now that I've got the k-map set up, where do I put that logic, on the diagram? Seeing as I'm supposed to have two stages, I'm guessing that for the first stage, I use the logic where Cin=0, and then connect that diagram to the next stage, using the logic where Cin=1?
I understand multi-bit adders, as I already pointed out. I know how Full Adders and Ripple Adders work and such.But you want to keep just rushing past the stuff you don't understand and it just keeps biting you in the ass down the road.
And for the record, I'm not an Engineer, my concentration is Software Development. And I'm kinda like, you know, a student, so of course I'm not going to know everything. No need to get all hostile, jeez.In class, that approach costs you points and grades. Out in the real world, that approach is going to get people killed, so if that is going to continue to be the way you want to approach engineering, please get the hell out of it.
Apparently you don't, not if you are talking about setting the values for the Cin inputs for anything other than the first stage.I understand multi-bit adders, as I already pointed out. I know how Full Adders and Ripple Adders work and such.
You've done it at every opportunity thus far, so there is a definite pattern there. Prove me wrong by simply stopping it.Not understanding one thing is not "rushing past everything I don't understand".
You don't think that people have died when software developers have taken to "guessing" and failing to make the effort to understand what their code is supposed to be doing? As for being a student, part of being a student is learning how to be a professional. At what point are you supposed to start trying to understand what you are doing? Will it magically happen once you have your degree? Or will you start taking it seriously only after a few plane loads of people have died because of your software bugs?And for the record, I'm not an Engineer, my concentration is Software Development. And I'm kinda like, you know, a student, so of course I'm not going to know everything. No need to get all hostile, jeez.
This from a man with the patience of Job. Time for sackcloth and ashes. I greatly admire your fortitude.Apparently you don't, not if you are talking about setting the values for the Cin inputs for anything other than the first stage.
You've done it at every opportunity thus far, so there is a definite pattern there. Prove me wrong by simply stopping it.
You don't think that people have died when software developers have taken to "guessing" and failing to make the effort to understand what their code is supposed to be doing? As for being a student, part of being a student is learning how to be a professional. At what point are you supposed to start trying to understand what you are doing? Will it magically happen once you have your degree? Or will you start taking it seriously only after a few plane loads of people have died because of your software bugs?
Since it is obvious you have no intention of doing the very simple thing I requested, I am done with you.
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