Discussion in 'Homework Help' started by coldashes, Jun 19, 2015.

1. ### coldashes Thread Starter New Member

Jun 19, 2015
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k-map: https://www.dropbox.com/s/5w77efs5x4z8p6o/20150619_190416.jpg?dl=0

I have to come up with I0-I3 for the kmap I posted above, but I am a little confused about how to create the cells for the partitioned map. In this picture the control signal is wx. Can someone please confirm that those are the correct value to circle and can someome tell me if I3 would be Xor or a NAND implementation I have some slides on the subject of substitution, but there are none similar to the situation I ran into in I3. Honestly I am a computer science major and have to take this course on logic design so please be patient with me as I really have tried to understand the course work but am struggling.

2. ### WBahn Moderator

Mar 31, 2012
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I'm a bit confused as to what I0 through I3 even are, although I think I can read between the lines enough to guess what the point is. Seems like a strange way of going about things, but maybe there's a rational reason. I3 would not be XOR (does XOR yield a 1 if both inputs are the same?). But it is was, or if it was something else, such as XNOR or IMP or NIMP, then MIGHT be able to use that gate as opposed to a NAND or and AND/OR/NOT implementation. That would depend on the constraints placed on your design, which we have no idea about.

As to being a computer science major being forced to take a logic design course, what's your complaint? You don't think that computer programs involve logic? I've seen lots of code that could have been done much more elegantly and efficiently if the programmer had simply paid attention in a logic design class somewhere.

3. ### coldashes Thread Starter New Member

Jun 19, 2015
4
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I was actually rather excited to take this course. I am not complaining about having to take it really, I definitely understand why it is important. Unfortunately the class is being poorly taught and is rather unorganized. This is just my opinion, but based off everyone in the class also being completely lost and taking this course for their second or third time I would imagine its not just me.

This might help clear some things up 2 (2) is the area I am speaking of.
labpg1: https://carousel.dropbox.com/photos/cc/NOClEAUhIEMN7Pl
labpg2: https://carousel.dropbox.com/photos/cc/BCvWnqR5n0zDPNt

Last edited: Jun 19, 2015
4. ### coldashes Thread Starter New Member

Jun 19, 2015
4
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2.(3) on page one is actually what I was talking about sorry.

5. ### WBahn Moderator

Mar 31, 2012
18,085
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Instead of posting links to third-party sites where you have uploaded images, it is preferred that you upload images directly to AAC. This is for several reasons. First, it makes it a lot easier on the people that are trying to offer you free assistance. Second, many of our members will not follow links to third party sites because of the potential for malware issues. Third, many times third-party content becomes unavailable over time and if it is uploaded here then it will remain available as long as AAC is.

So, if possible, take your images and size them to something reasonable and then upload them with your post.

6. ### coldashes Thread Starter New Member

Jun 19, 2015
4
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I think it would be pretty damn funny if I was asking for help and then linked a virus in my post. Thanks for the laugh, but it seems like I am unable to really explain what I need help with so I will just try to figure it out. Thanks for trying to help. I'm sure it will workout out maybe I do not have a firm grasp on this stuff, but I still have an A average in the class.

7. ### WBahn Moderator

Mar 31, 2012
18,085
4,917
Actually, it is quite common. We get spam posted here a dozen or two times a day and many of the links are malicious. If you think about it, someone that wants to link to viruses is going to want to come off as sounding like an earnest poster just asking for help. Sounding genuine but being sleazy is the whole basis for phishing attacks.

The print in your image is a bit too small for my aging eyes to read. If you want to post an image that just has the part that is relevant, I will be happy to look at it. But I suspect you will manage either way as you seem to have a general grasp.

8. ### WBahn Moderator

Mar 31, 2012
18,085
4,917
Which set of equations are you trying to implement?

What you are being asked to do is consistent with what I was guessing in my first reply. Usually you use a separate K-map for each input to the mux, but the way you are showing it is fine.