1. CS 206D Computer Organization
Lab4
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2. Logic instructions
Logic Instructions
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3. AND destination, source OR destination, source XOR destination, source
Logic instructions
AND destination, source
OR destination, source
XOR destination, source
NOT destination
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4. AND
The AND instruction can be used to clear specific Destination bits while preserving the others.
A zero mask bit clears the corresponding Destination bit
A one mask bit preserves the corresponding destination bit.
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5. OR
The OR instruction can be used to set specific Destination bits while preserving the others.
A one mask bit sets the corresponding Destination bit
A zero mask bit preserves the corresponding Destination bit.
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6. XOR
The XOR instruction can be used to invert specific Destination bits while preserving the others.
A one mask bit inverts the corresponding Destination bit
A zero mask bit preserves the corresponding Destination bit.
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7. Programming questions – q 1
Declare data and display prompt message
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8. Programming questions – q 1 (Cont.)
Read binary number
We assume that the input characters are either ‘1’ , ‘0’ or carriage return. And at most 16 bits are input.
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9. Programming questions – q 1 (Cont.)
Output the content of BX in HEX.
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