3.3.1. Program Status Word Overview

Try these first

1. 1.

   What does the overflow flag indicate?

   Hint

   Think about what happens when numbers are too large.

2. 2.

   What is a carry flag?

   Hint

   Consider operations involving addition of large numbers.

3. 3.

   What does the overflow flag signify?

   • a) Valid operation
   • b) Exceeding maximum value
   • c) Result is zero

   Hint

   Relate it to results that cannot fit.

4. 4.

   True or False: The sign flag indicates if a number is zero.

   • True
   • False

   Hint

   Recall what the zero flag measures.

5. 5.

   You are performing operations in a 4-bit system. What will happen if you add 7 and 1? Explain in detail.

   Hint

   Consider the limits of your bit-width system and what values are representable.

6. 6.

   Create a code snippet that checks the overflow flag after performing an addition. What should the code do if the overflow flag is set?

   Hint

   Think about mechanisms of error handling in programming.