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8051 Architectural Specification and Functional Description
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| a: | 
 | REGISTER BANK 0 | 
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| 
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 | DRIVERS | 
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 | CONTROL | 
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 | ENGINE | 
 | Iv | 
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 | INSTRUCTION | 
 | VL | 
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 | DECODER | 
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| ~"r | 
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 | '" | ~ | 
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 | • | ||
| 
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 | ~L | 
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 | |||||||
| CIRCUITRY | q | 
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 | J~ | rr | l}, | ||||
| t | + | 
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 | |||||
| & | 
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| osc | 
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| TIMING | 
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 | I | I | I | 
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 | I | 
 | 1 | r | 
| x | X | E | A | P | D | 
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 | 
 | PORTO0 | |
| T | T | A | L | S | 
 | 
 | 
 | 
 | 
 | 
 | 
 | |||
| A | A | / | E | E | 
 | PORT 3 | 
 | PORT2 | 
 | |||||
| L | L | V | / | N | PORT 1 | 
 | D | 
 | D | |||||
| 1 | 2 | D | P | 
 | 
 | 
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| 
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 | D | R | 
 | 
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| 
 | 
 | 
 | o | 
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 | 
 | 
G
4K ·8 NONE (8031) ROM (8051V EPROM (87511
DRIVERS
~~
I
~
17- ~
R V V
S C S
T C S
/
V
P
D
Figure 2.11. 8051 Family Functional Block Diagram
10
