Introduction to Computer Science
CSCI 125, Spring 2004
Test 3
- Please answer each question carefully and thoughtfully.
- Please use as much paper as you wish and answer in any order, but make
sure that you label each question.
- Make sure that your name is on each page.
- Make sure that you answer all questions.
- Point values for each question are noted by the question.
- When performing mathematics, please show all work. If the work is
not present and the answer is wrong, no partial credit will be assigned.
- (5 points)
- Draw a abstract diagram of a full adder.
- Label all of the inputs and the outputs on this diagram.
- Describe what this circuit does.
(You do not need to draw any gates for this question)
- (5 points) Give an algorithm to add two 4 bit binary numbers.
- Give an example of adding two numbers.
- Draw a diagram on how this can be performed using a full adder.
- Describe in English what happens in this circuit
- (10 points) Given the boolean expression f(x,y,z) = (xz)'+y'z
- Create a truth table for the expression.
- Draw a circuit that implements the expression
- (5 points) For the exclusive or function, give the
- boolean expression
- logic symbol
- truth table
- (4 points) Draw a picture of a cpu. Include the following items
- ALU, CU, MMU, IR, PC, REG
- (6 points) For each item in the previous question name and give a one sentence description
of what that item does.
- (5 points) Describe the fetch-decode-execute cycle.
- (10 points) For each of the following, name and describe the units used to measure the item and give a range of the size of the item in a modern personal computer.