Assignment
Problem 1
Represent each o f the following decimal numbers i n each o f the following binary representations using 8-bits:
1. Signed magnitude 2 . One's complement 3 . Two's complement
A. 8 2
B. - 1 7
C. Add the t w o ' s complement o f A and B above and then convert the result t o decimal.
Problem 2
Using the 1 4 - b i t floating point model, what i s the Signed Magnitude Representation -normalized & biased for: - 1 0 0 . 3 7 5
A. What is the representation of the Sign?
B. What is the representation of the Exponent?
C. What is the representation of the Significant?
D. What is the entire 1 4 - bit representation?
Problem 3
Complete the chart below for the following questions for the P e p / 8 machine language instructions given. Each Instruction starts from the Original Content ( i . e . each instruction is independent and i s not based o n the previous instruction). You will need t o jump ahead t o Chapter 6 t o determine ( D ) for one o f the instructions.
A: Accumulator X : Index Register
Me m [ 0 A3 F ] : Contents of Memory 0A3F Mem [ 2A41 ] : Contents o f Memory 0A41
A. What does the instruction do ? ( Do )
B. Which register does it specify? (Register)
C. Which addressing mode does it specify? (Mode)
D. Given the original content, what is the content after the execution of the following instructions:
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Do
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Rgister
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Mode
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A
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X
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Mem[0A3C]
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Mem[A42]
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Original Content
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10B6
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FE25
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0A41
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AF30
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Insturction
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792A42
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E12A42
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A90A3C
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C22A42
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Problem 4
Determine the output o f the following machine-language program by running it in Pep/8. The left column in each part is the memory address of the first byte on the line:
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Address
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Instrution
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Description
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0000
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C1000C
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0003
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18
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0004
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F1000B
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0007
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51000B
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000A
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00
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000B
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00
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000C
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FFDA
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A. Submit the code with comments describing each line.
B. What is the output of the program?
C. The instruction at address 0003 is a unary instruction. What does that mean?
D. What is the instruction at 0003 doing? Give the binary value of the accumulator before and after the command.
Problem 5
Write a machine-language program t o output your first name o n the output device. Write it in a format suitable for the loader and execute it on the PEP/8 simulator. You may only use instructions in Fig 4.6. You shall submit
A. A written algorithm
B. Your commented program similar t o the Machine Language (hex) of Fig 4.35
C. The hexadecimal program suitable for the P e p / 8 loader. (Cut & paste the text into your document s o I can check your code)
D. A screenshot o f your program output screen
Problem 6
Write a machine-language program t o add the three numbers 6,-7 and 4 and output the sum o n the output device. Note-the inputs can be hard coded in data storage at the end of your code. The accumulator holds 16 bits so use 16 bit Two's Complement for the - 7 and do not use the subtract instruction. Write it in a format suitable for the loader and execute it on the PEP/8 simulator. You may only use instructions in Fig 4.6. You shall submit:
A. A written algorithm
B. Your commented program similar t o the Machine Language ( h e x ) of Fig 4 . 3 5
C. The hexadecimal program suitable for the Pep/8 loader. (Cut & paste the text into your document s o I can check your code)
D. A screenshot of your program output screen
E. Explain the range of numbers that this will work correctly.