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Intel387
TM
SX Math CoProcessor
CONTENTS
PAGE
1.0 PIN ASSIGNMENT
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1.1 Pin Description Table
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2.0 FUNCTIONAL DESCRIPTION
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2.1 Feature List
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2.2 Math CoProcessor Architecture
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2.3 Power Management
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2.3.1 Dynamic Mode
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2.3.2 Idle Mode
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2.4 Compatibility
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2.5 Performance
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3.0 PROGRAMMING INTERFACE
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3.1 Instruction Set
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3.1.1 Data Transfer Instructions
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3.1.2 Arithmetic Instructions
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3.1.3 Comparison Instructions
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3.1.4 Transcendental
Instructions
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3.1.5 Load Constant Instructions
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3.1.6 Processor Instructions
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3.2 Register Set
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3.2.1 Status Word (SW) Register
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3.2.2 Control Word (CW)
Register
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3.2.3 Data Register
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3.2.4 Tag Word (TW) Register
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3.2.5 Instruction and Data
Pointers
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3.3 Data Types
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3.4 Interrupt Description
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3.5 Exception Handling
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3.6 Initialization
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3.7 Processing Modes
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3.8 Programming Support
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CONTENTS
PAGE
4.0 HARDWARE SYSTEM
INTERFACE
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4.1 Signal Description
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4.1.1 Intel386 CPU Clock 2
(CPUCLK2)
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4.1.2 Intel387 Math CoProcessor
Clock 2 (NUMCLK2)
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4.1.3 Clocking Mode (CKM)
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4.1.4 System Reset (RESETIN)
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4.1.5 Processor Request
(PEREQ)
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4.1.6 Busy Status (BUSY
Y
)
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4.1.7 Error Status (ERROR
Y
)
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4.1.8 Data Pins (D15–D0)
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4.1.9 Write/Read Bus Cycle
(W/R
Y
)
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4.1.10 Address Stobe (ADS
Y
)
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4.1.11 Bus Ready Input
(READY
Y
)
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4.1.12 Ready Output
(READYO
Y
)
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4.1.13 Status Enable (STEN)
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4.1.14 Math CoProcessor Select 1
(NPS1
Y
)
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4.1.15 Math CoProcessor Select 2
(NPS2)
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4.1.16 Command (CMD0
Y
)
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4.1.17 System Power (V
CC
)
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4.1.18 System Ground (V
SS
)
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4.2 System Configuration
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4.3 Math CoProcessor Architecture
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4.3.1 Bus Control Logic
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4.3.2 Data Interface and Control
Unit
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4.3.3 Floating Point Unit
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4.3.4 Power Management Unit
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