Intel 80386 User Manual

TABLE OF CONTENTS
CHAPTER 1
Page
SYSTEM OVERVIEW
1.1 Microprocessor ............................................................................................. 1-1
1.2 Coprocessors.................................................................................................. 1-3
1.3
Integrated System Peripheral .................... l................................................... 1-4
1.4 Cache Controller ........................................................................................... 1-5
1.5 Clock Generator ............................................................................................ 1-5
1.6
8086/80286 Family Components .... ........... ................. ..... ......... ........... ......... 1-5
CHAPTER 2
INTERNAL ARCHITECTURE
2.1 Bus Interface Unit ........ ............................. ....... ....... ........................ ............... 2-2
2.2
Code Prefetch Unit ........................................................................................ 2-3
2.3
Instruction Decode Unit ......................... ......... ............ ..... ......... ...... ..... .......... 2-3
2.4 Execution Unit ............................................................................................... 2-3
2.5 Segmentation Unit ......................................................................................... 2-4
2.6 Paging Unit .................................................................................................... 2-4
CHAPTER 3
LOCAL BUS INTERFACE
3.1 Bus Operations ............ ........... ........... ............. ............................... ............... 3-2
3.1.1 Bus States ........................... ........... ............ ................................ ............... 3-4
3.1.2 Address Pipelining
.. ............... ............................................... ....... ............... 3-5
3.1.3 32-Bit Data Bus Transfers
and Operand Alignment .... ...... ...... .......... ......... 3-5
3.1.4
Read Cycle .. ............... ............... .............. ...... ........... .................. ................ 3-10
3.1.5 Write Cycle .................. ................. ................. ............................. ..... ........... 3-13
3.1.6 Pipelined Address
Cycle ......... .............. ......... ............... .............. ..... ........... 3-14
3.1.7
Interrupt Acknowledge Cycle .................. ...... ............ ................. ..... ........... 3-17
3.1.8 Halt/Shutdown Cycle ........ ................ ...... .................. ................... .............. 3-18
3.1.9 BS16 Cycle ................................................................................................ 3-19
3.1.10 16-Bit Byte Enables and Operand Alignment ........ ........ .................. ......... 3·20
3.2 Bus Timing .............. .......... ................ .................. ........................... ............... 3-22
3.2.1 Read Cycle Timing ..................................................................................... 3-24
3.2.2 Write Cycle Timing ..................................................................................... 3-24
3.2.3 READY# Signal Timing .............................................................................. 3-25
3.3 Clock Generation ....... ............ ..... ............. ....................................... ............... 3-26
3.3.1 82384 Clock Generator .............. ........ ........... ............... ............... ............... 3-26
3.3.2
Clock Timing . ....... ................... ........ ..... ....... ................................ ..... .......... 3-26
3.3.3 Crystal Oscillator
Clock Generator .. ......................... ....... ...... ...... ....... ........ 3-27
3.4
Interrupts .......... .......... .............. .......... ........ ........................ ............ ....... ........ 3-29
3.4.1 Non-Maskable Interrupt (NMI) ............... ......................... ...... ...... ................ 3-30
3.4.2 Maskable Interrupt (INTR) .......................................................................... 3-31
3.4.3 Interrupt Latency ........................................................................................ 3-31
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Intel 80386 Specifications

General

Clock Speed	12 MHz to 40 MHz
Transistor Count	275, 000
Addressable Memory	4 GB
Data Bus Width	32-bit
Instruction Set	x86
Introduction Date	October 17, 1985
Virtual Memory	Yes
Operating Modes	Real mode, Protected mode, Virtual 8086 mode
Manufacturer	Intel
Model	80386
Address Bus Width	32-bit
Voltage	5V
Manufacturing Process	1.5 µm
Cache	No on-chip cache
FPU	Optional (80387)
Bus Interface	32-bit
Process Technology	CHMOS III
Package	PGA