{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Proj2 - carry and then 8 times to do the add Be sure that...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
1 ECE 631: Digital Systems Test and Testable Design Project #2 Use time-frame expansion and the extended D-algorithm to find a test for the s-a-0 fault in the sequential circuit shown below. A(n) and B(n) are the two primary inputs (x 1 and x 2 in the notation of the book). S(n) and C(n+1) are the two primary outputs (z 1 and z 2 in the notation of the book). Remember that the faulty circuit has the same fault in every copy of the combinational logic. It is necessary to stimulate at least one of these faults to have a test - it is not necessary to stimulate the fault in every copy of the expanded faulty circuit (although every copy of the faulty gate should give faulty output). There are no faults in any copy of the fault-free circuit. The circuit is a full adder configured to be used as a ripple-carry adder. Suppose that this circuit is part of an 8-bit microcontroller. Under normal operation, this circuit would be cycled 9 times to do an add (once with input 00 to clear the
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: carry and then 8 times to do the add). Be sure that the test you find works the same whether the initial carry value C(0) is 0 or 1. This can be accomplished by being sure that C(n) is set to X at the start of the test generation. Alternatively, one could set C(n) to 0 initially and use the extended D-algorithm to find a test. Then C(n) would be initialized to 1 and the output from the test pattern would be examined to see if the error on at least one primary output was the same for C(0) = 0 and C(0) = 1. In order for the error to be the same it should be D in both cases or D-bar in both cases (on the same primary output). Show simulation output proving that your test works for both initial values of the carry bit. 2 s-a-0 A ( n ) S ( n ) B ( n ) C ( n + 1 ) C ( n ) F F...
View Full Document

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern