Section 6.1
Review Questions
Data Representation
  1. Are all character representation codes 8-bits long?
answer...
No, some early ones were 6 bits and others 7 bits.
  1. Name a famous character representation code other than ASCII. Who uses it?
answer...
EBCDIC, used by IBM mainframes
  1. Which symbol does 64 stand for? (From here on out we will use only ASCII).
answer...
@
  1. Write down the code for }.
answer...
125
  1. How many codes are reserved for special graphics characters?
answer...
In 8-bit ASCII, 128 codes are reserved for graphics. They are all in the range 128-255.
  1. Write out your name in ASCII.
answer...
Mark = 77 95 114 107
  1. What does the following sequence of ASCII characters spell? 
     01010010  01000101  01001100  01001001  01000101  01000110
answer...
01010010  01000101  01001100  01001001  01000101  01000110
    R         E         L         I         E         F
  1. Why did the designers of ASCII use 65 for 'A'?
answer...
There was no reason. It was purely arbitrary.
  1. Given that 65 is 'A', why would the designers choose 66 for 'B'? Why not 24?
answer...
Codes for letters should be consecutive and ascending so that comparisons work in a logical sense similar to alphebetization. If the code for 'B' were less than the code for 'A', then the computer could not alphabetize correctly.
  1. The new Unicode standard which is used by Java has 16-bit characters. How many different symbols can this standard represent?
answer...
65,536
  1. If you wanted a terminal to "beep" or "ring its bell," which ASCII symbol would you send to it?
answer...
7 (BEL)
  1. What are some of the uses of the special control characters?
answer...
to control printers, monitors, modems and other peripherals
  1. Where in the range of ASCII codes did they assign these control characters?
answer...
from 0 to 31
  1. What is odd about EBCDIC's assignment of letters to numbers?
answer...
there are breaks in their alphabet. 'j' may be something like 59 but 'k' is something like '64'.