Compaq EN Series - Page 8

Technical Reference Guide
Compaq Deskpro EN Series of Personal Computers
Desktop and Minitower Form Factors
Third Edition - September 1998
v
5.5 PARALLEL INTERFACE................................................................................................... 5-20
5.5.1 STANDARD PARALLEL PORT MODE ..................................................................... 5-20
5.5.2 ENHANCED PARALLEL PORT MODE..................................................................... 5-21
5.5.3 EXTENDED CAPABILITIES PORT MODE............................................................... 5-21
5.5.4 PARALLEL INTERFACE PROGRAMMING.............................................................. 5-22
5.5.5 PARALLEL INTERFACE CONNECTOR ...................................................................5-26
5.6 KEYBOARD/POINTING DEVICE INTERFACE ...............................................................5-27
5.6.1 KEYBOARD INTERFACE OPERATION ................................................................... 5-27
5.6.2 POINTING DEVICE INTERFACE OPERATION .......................................................5-29
5.6.3 KEYBOARD/POINTING DEVICE INTERFACE PROGRAMMING ......................... 5-29
5.6.4 KEYBOARD/POINTING DEVICE INTERFACE CONNECTOR................................ 5-33
5.7 UNIVERSAL SERIAL BUS INTERFACE........................................................................... 5-34
5.7.1 USB KEYBOARD CONSIDERATIONS...................................................................... 5-34
5.7.2 USB CONFIGURATION.............................................................................................. 5-34
5.7.3 USB CONTROL........................................................................................................... 5-35
5.7.4 USB CONNECTOR ..................................................................................................... 5-35
CHAPTER 6 AUDIO SUBSYSTEM ......................................................................................................
6.1 INTRODUCTION.................................................................................................................. 6-1
6.2 FUNCTIONAL DESCRIPTION.............................................................................................6-2
6.2.1 PCM AUDIO PROCESSING..........................................................................................6-4
6.2.2 FM SYNTHESIS AUDIO PROCESSING.......................................................................6-7
6.3 PROGRAMMING.................................................................................................................. 6-8
6.3.1 CONFIGURATION........................................................................................................ 6-8
6.3.2 CONTROL..................................................................................................................... 6-9
6.4 SPECIFICATIONS.............................................................................................................. 6-11
CHAPTER 7 POWER SUPPLY AND DISTRIBUTION.......................................................................
7.1 INTRODUCTION.................................................................................................................. 7-1
7.2 POWER SUPPLY ASSEMBLY/CONTROL.......................................................................... 7-1
7.2.1 POWER SUPPLY ASSEMBLY..................................................................................... 7-2
7.2.2 POWER CONTROL....................................................................................................... 7-3
7.3 POWER DISTRIBUTION...................................................................................................... 7-5
7.3.1 3.5/5/12 VDC DISTRIBUTION...................................................................................... 7-5
7.3.2 LOW VOLTAGE DISTRIBUTION................................................................................7-6
7.4 SIGNAL DISTRIBUTION..................................................................................................... 7-7
CHAPTER 8 BIOS ROM .......................................................................................................................
8.1 INTRODUCTION.................................................................................................................. 8-1
8.2 BOOT/RESET FUNCTIONS................................................................................................. 8-2
8.2.1 BOOT BLOCK............................................................................................................... 8-2
8.2.2 QUICKBOOT.................................................................................................................8-2
8.2.3 SILENTBOOT ............................................................................................................... 8-2
8.2.4 RESET...........................................................................................................................8-2