1) What would be the encoded version of the message

xxy yyx xxy xxy yyx

if LZW compression, starting with the dictionary containing x, y and a space (as described in Section 1.8 of your textbook) were used. Show both the message and the final dictionary.

2) The following message was compressed using LZW compression with the dictionary given below. What is the decompressed message? 22123113431213536 Dictionary

encoding	Character
1	x
2	y
3

3) Encode the following sentence in ASCII using even parity by adding a parity bit at the high- order (left) end of each character code:

The total cost is $7.25.

To help here are the first two characters:

T 101010100

h 101101000

e

t

o

.

.

.

4) Using the error-correcting code given to the right, decode the following words:

a. 111010 110110

b. 101000 100110 001100

c. 011101 000110 000000 010100

d. 010010 001000 001110 101111 000000 110111 100110

e. 010011 000000 101001 100110

5) List the three main parts of a CPU and briefly describe what each one does.

6) The following are instructions written in the machine language described in Appendix C. Translate them into English.

Example: 18AC = LOAD register 8 with the contents of memory cell AC

a. 7123

b. 70E1

c. A304

d. B100

e. 2BCD

7) Translate the following instructions from English into the machine language described in Appendix C.

a. LOAD register 6 with the hexadecimal value 77.

b. LOAD register 7 with the contents of memory cell 77

c. JUMP to the instruction at memory location 24 if the contents of register 0 equals the value in register A

d. ROTATE register 4 three bits to the right

e. AND the contents of registers E and 2 leaving the result in register 1.

8) What instruction(s) would change in Figure 2.7 in your textbook if the values added were encoded using floating-point, rather than twos complement? What would the correct instruction(s) be, encoded as a hexadecimal value?

9) Encode the following values using the 8-bit floating-point format described in the textbook. Indicate each case in where a truncation error occurs.

a) -7

b)

c) -3

d) 7?32

e) 31?32