InClass

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In-Class 5 Answers

• As assigned in class on Oct. 7

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Problem 12

• Suppose the memory cells at addresses 00
  through 03 in the machine described in Appendix C
  contain the following bit patterns

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Problem 12 continued

• a. Translate the first instruction into English.
• Answer Place the value 05 in register 4.
• b. If the machine is started with its program
  counter containing 00, what bit pattern is in
  register 4 when the machine halts?
• Answer 05

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Problem 13

• Suppose the memory cells at addresses 00
  through 02 in the machine described in Appendix C
  contain the following bit patterns

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Problem 13 continued

• a. What would be the first instruction
  executed if we started the machine with its
  program counter containing 00?
• Answer 241B
• b. What would be the first instruction executed
  if we started the machine with its program
  counter containing 01?
• Answer 1B34

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Problem 14

• Suppose the memory cells at addresses 00 through
  05 contain the following bit patterns.

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Problem 14 continued

• When answering the following questions, assume
  that the machine starts with its program counter
  equal to 00.
• a. Translate the instructions that are executed
  into English.
• 1004 -- Load register 0 with the contents of
  memory cell 04
• 3045 -- Store the contents of register 0 in
  memory cell 45.
• C000 -- Halt

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Problem 14 continued

• b. What bit pattern is in the memory cell at
  address 45 when the machine halts?
• Answer C0
• c. What bit pattern is in the program counter
  when the machine halts?
• Answer 06

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Problem 15

• Suppose the memory cells at addresses 00
  through 09 contain the following bit patterns

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Problem 15 continued

• Assume that the machine starts with its program
  counter containing 00
• a. What will be in the memory cell at address 00
  when the machine halts?
• Answer 29
• b. What bit pattern will be in the program
  counter when the machine halts?
• Answer 0A