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20
bit address can access 1 MB of memory
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16
bit registers can only access 64KB of
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memory
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Need
some strategy for accessing more memory!
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Approach
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Use
value in segment + offsets from register
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Notation
SEG:OFF
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Both
value in segment and offset are 16 bits
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To
create a 20 bit address
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(1)
Shift segment value left by 4 bits (shift in 0s)
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(2)
Add offset to get 20 bit value
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