80286 BASE ARCHITECTURE

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,

 

20000 CS

8000 r-----..,

 

MAIN

8600 r-----.,

PROCEDURE

PROCEDURE

A

 

0 _____...

 

_____I

0'"-____..1

 

7253051

DATA (B)

 

DATA (A)

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2000 ~----..,

 

 

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CURRENTLY

ACCESSIBLE

G3010B

Figure 2-1. Segmented Virtual Memory

A byte is 8 contiguous bits starting on an addressable byte boundary. The bits are numbered 0 through 7, starting from the right. Bit 7 is the most significant bit:

o

I I i

BYTE

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A word is defined as two contiguous bytes starting on an arbitrary byte boundary; a word thus contains 16 bits. The bits are numbered 0 through 15, starting from the right. Bit 15 is the most significant bit. The byte containing bit 0 of the word is called the low byte; the byte containing bit 15 is called the high byte.

15

0

I : :~IGH:B+: : I : :+W:BY+: : I

LOCATION N+ 1

LOCATION N

2-2

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Image 28
Intel 80287, 80286 manual 8000 r