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Figure 5.6
Direct mapping.
Example:
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24b real address
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8B physical word
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16KB cache
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64B line
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\ 256 line (16K/64) in cache
Advantage Cache directory and cache are simultaneously accessed
Disadvantage Line in memory location maps into only one line in cache.
Steps of operation:
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1. Translate VPN to RPN with TLB.
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2. Access cache array and directory simultaneously and compare tag with directory entry to ensure correct line is accessed.
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3. Access cache array with index and offset (11b) bits.
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4. If compare valid, enable data to go to processor.

 
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