Transcript 1-bit adder

COMPUTER ARCHITECTURE &
OPERATIONS I
Instructor: Yaohang Li
Review
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Last Class
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Representation of Integer
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Addition
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Subtraction
This Class
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1-bit ALU Unit
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Assignment 2
Next Class
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Design of ALU
Arithmetic Logic Unit
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Arithmetic Logic Unit (ALU)
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Heart of a CPU
Operations
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Arithmetic operations
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Addition
Subtraction
Logical operations
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NOT
AND
OR
1-bit Logical Unit for AND and OR
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1-bit logical unit for AND and OR
1-bit adder
1-bit adder truth table
Simplifying 1-bit adder
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If a and b and CarryIn are true, then the three
other terms are true as well
can be simplified as
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Values when CarryOut is true
Logic of CarryOut Bit
Logic of Sum Bit
Overall 1-bit ALU
Summary
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1-bit Adder
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Logical Design
What I want you to do
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Review Appendix B