Section 6.3
Review Questions
Signed binary numbers (integers)
  1. What are the two major ways to encoding signed binary numbers discussed in this section?
answer...
sign-magnitude and 2's complement
  1. What is -15 written out in 8 bits using sign-magnitude form?
answer...
10001111
  1. Suppose your registers were only 16 bits long. Could you put -500,000 into a register using sign-magnitude form?
answer...
No way! 500,000 requires 19 bits for the magnitude alone and the sign bit would up that to 20.
  1. What do we call it when we add 0s to the front end of a number, which does not change its value, so that it will have the required number of bits?
answer...
padding out
  1. What spurious number exists in 1's complement but not 2's complement?
answer...
-0
  1. How do you go from ordinary binary to 1's complement? For example, 01111 is 15. What would -15 be?
answer...
if the number is negative, write out the absolute value in binary and then invert all the bits (change 0s to 1s and 1s to 0s)