Digital Logic halp: Flip Flops and counting level changes at clock transitions

[Vandole]

My teacher assigned this for bonus points without teaching it. I missed a quiz that he assigned earlier this semester because of a funeral so I kind of need to do this, however I don't understand it at all. Any help or explaining of this would be much appreciated.

[Teorem]

This is a little tough to explain without knowing what you already understand and giving it away completely...

You have a two edge-triggered flip-flops: a JK flip-flop and a T flip-flop. The output of these flip-flops depends on the inputs (J and K, or T) and will either be 0, 1, the current state (usually denoted Q), or the opposite of the current state (Q-bar). It also depends on the CLR (clear) input, which, according to the diagram, is activated when the CLR input is low (0).

The diagram also indicates that the clocks are negative-edge triggered, so inputs will be collected on the falling, 1-to-0 edge of CLK. Any transitions in the output--Q1, Q1-bar, Q2, Q2-bar signals--will occur after some propagation delay, which should be reflected in your timing diagram.

Your class materials should have the truth-tables for JK flip-flops and T flip-flops, and it should make more sense for your timing diagram if you list out what the logical values of K and Z are.

Spoiler: show

J = 0, K = 0: Q(t+1) = Q(t) (output stays the same)
J = 0, K = 1: Q(t+1) = 0 (reset)
J = 1, K = 0: Q(t+1) = 1 (set)
J = 1, K = 1: Q(t+1) = Q-bar(t) (output flips)

T = 0: Q(t+1) = Q(t) (output stays the same)
T = 1: Q(t+1) = Q-bar(t) (output flips)

Should be able to provide more help with a better idea of what you're unclear on so far.

[Vandole]

The teacher called us all idiots and cancelled the credit lol

[Korietsu]

Plug it into xilinx or circuitworks and call it a day. However, the answer to this problem is contained in the answer book for the computer architecture/org and design of computers book by patterson and hennesy. this was a test problem for us in 2007.

[Vandole]

THIS IS A 100 LEVEL COURSE, WHY AM I BEING ASKED STUFF FROM COMPUTER ORG!?

[Athas]

Basic logic gates and flip flops are 100 level material. Comp Org courses are typically more CPU level material.

At least it was so at my school.

[Teorem]

This kind of material was covered in my second semester EE course when I was an undergrad, as well. I strongly recommend working through the problem and NOT just plugging it into Powerview/ePD/ISE/Modelsim/whatever because it really is not a difficult problem at all and covers fundamentals of synchronous circuits that you likely really should know.

[Korietsu]

THIS IS A 100 LEVEL COURSE, WHY AM I BEING ASKED STUFF FROM COMPUTER ORG!?

The book covers not only architecture, organization, and machine level code but the design of everything up to the fast adder and some more complex things like multiplication using fast adders. I was handed a 4000 level course test for a data structures class on April 1st. I nearly freaked out because it would be an instant ace. The rest of the class barring my CE buddy was freaking the fuck out haha. Instead he gave us the stupid data structures test and the whole mood was switched.

Don't worry, its not a complex problem. Just have to map each input manually and run the clock. Determine how the clock runs the two flip flops and it writes itself.

And buy the book. Best reference tool ever, useful in probably half the EE/CE/CS courses you take.

[Abandon]

A school in the navy taught me this, your school sucks

[Korietsu]

I'd say he's taking an into to Digital logic class, rather than the applied class like Digital Systems. This is pretty standard 100 level stuff.

[Brill Weave]

A school in the navy taught me this, your school sucks

Did they teach you how to cover up murdering innocent little Okinawan schoolgirls?

[Brill Weave]

SUCK IT!

[Teorem]

And buy the book. Best reference tool ever, useful in probably half the EE/CE/CS courses you take.

Have you read the current (fifth) edition of the Hennessy & Patterson book? I have a copy of the third edition and was considering dropping the $50 to get a very much lighter Kindle version of the latest edition.

[Deadgye]

I know your teacher pulled it already, but I made you a pretty picture with color coding so you can see how I would do it. Top dot color first, and then so on. Assuming I did it correctly since I didn't double check shit. Clear is an async active low, flipflops are negative edge triggered, K1 is equal to Q2, T2 is equal to notQ1.

Spoiler: show

If you have any other problems/questions with this type of material shoot me a PM, especially if you make a thread so I notice it. If I'm not swamped I'll gladly help explain stuff. Digital is <3, anal OG is orz.

[Korietsu]

Have you read the current (fifth) edition of the Hennessy & Patterson book? I have a copy of the third edition and was considering dropping the $50 to get a very much lighter Kindle version of the latest edition.

I had the updated 4th back in 07? Not much changes other than the addition of new Architectures like the ivy bridge and sandy bridge.