Compaq 4000N User Manual
Page 6

Technical Reference Guide
Compaq Deskpro 4000N and 4000S Personal Computers
First Edition – September 1997
iv
CHAPTER 4 SYSTEM SUPPORT.........................................................................................................
4.1
INTRODUCTION.................................................................................................................. 4-1
4.2
PCI BUS OVERVIEW ........................................................................................................... 4-2
4.2.1
PCI CONNECTOR......................................................................................................... 4-3
4.2.2
PCI BUS MASTER ARBITRATION.............................................................................. 4-4
4.2.3
PCI BUS TRANSACTIONS........................................................................................... 4-5
4.2.4
OPTION ROM MAPPING ............................................................................................. 4-8
4.2.5
PCI INTERRUPT MAPPING ......................................................................................... 4-9
4.2.6
PCI CONFIGURATION............................................................................................... 4-10
4.3
ISA BUS OVERVIEW......................................................................................................... 4-11
4.3.1
ISA CONNECTOR ...................................................................................................... 4-12
4.3.2
ISA BUS TRANSACTIONS......................................................................................... 4-13
4.3.3
DIRECT MEMORY ACCESS...................................................................................... 4-15
4.3.4
INTERRUPTS.............................................................................................................. 4-18
4.3.5
INTERVAL TIMER ..................................................................................................... 4-22
4.3.6
ISA CONFIGURATION............................................................................................... 4-22
4.4
SYSTEM CLOCK DISTRIBUTION .................................................................................... 4-23
4.5
REAL-TIME CLOCK AND CONFIGURATION MEMORY............................................... 4-24
4.5.1
CONFIGURATION MEMORY BYTE DEFINITIONS ................................................ 4-25
4.6
I/O MAP AND REGISTER ACCESSING............................................................................ 4-41
4.6.1
SYSTEM I/O MAP ...................................................................................................... 4-41
4.6.2
87307 I/O CONTROLLER CONFIGURATION ........................................................... 4-42
4.7
SYSTEM MANAGEMENT SUPPORT ............................................................................... 4-44
4.7.1
FLASH ROM WRITE PROTECT ................................................................................ 4-44
4.7.2
PASSWORD PROTECTION........................................................................................ 4-45
4.7.3
I/O SECURITY ............................................................................................................ 4-46
4.7.4
USER SECURITY........................................................................................................ 4-46
4.7.5
TEMPERATURE SENSING ........................................................................................ 4-47
4.7.6
POWER MANAGEMENT ........................................................................................... 4-48
CHAPTER 5 INPUT/OUTPUT INTERFACES .....................................................................................
5.1
INTRODUCTION.................................................................................................................. 5-1
5.2
ENHANCED IDE INTERFACE ............................................................................................ 5-1
5.2.1
IDE PROGRAMMING................................................................................................... 5-1
5.2.2
IDE CONNECTORS ...................................................................................................... 5-8
5.3
DISKETTE DRIVE INTERFACE........................................................................................ 5-10
5.3.1
DISKETTE DRIVE PROGRAMMING ........................................................................ 5-11
5.3.2
DISKETTE DRIVE CONNECTOR.............................................................................. 5-14
5.4
SERIAL INTERFACES ....................................................................................................... 5-15
5.4.1
RS-232 INTERFACE ................................................................................................... 5-15
5.4.2
SERIAL INTERFACE PROGRAMMING .................................................................... 5-16
5.5
PARALLEL INTERFACE ................................................................................................... 5-21
5.5.1
STANDARD PARALLEL PORT MODE ..................................................................... 5-21
5.5.2
ENHANCED PARALLEL PORT MODE ..................................................................... 5-22
5.5.3
EXTENDED CAPABILITIES PORT MODE ............................................................... 5-22
5.5.4
PARALLEL INTERFACE PROGRAMMING .............................................................. 5-23
5.5.5
PARALLEL INTERFACE CONNECTOR ................................................................... 5-27