Specifications

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CHAPTER 3 - SOFTWARE CONFIGURATION
3.1 Introduction........................................................................................................................... 3-1
3.1.1 Conventions............................................................................................................ 3-1
3.2 Operation with DOS.............................................................................................................. 3-2
3.2.1 Configuration Options ............................................................................................ 3-3
3.2.2 Little Board/286 Utilities Overview....................................................................... 3-3
3.2.3 Two Special Files ................................................................................................... 3-4
3.2.4 The Ampro SETUP Function ................................................................................. 2-4
3.3 CPU and BUS Speed Initialization ....................................................................................... 3-5
3.3.1 Fixed Speed Operation (Using SETUP)................................................................. 3-5
3.3.2 Variable Speed Operation (Using SETSPEED) ..................................................... 3-5
3.4 Using a Parallel Printer ......................................................................................................... 3-6
3.5 Using the Serial Ports............................................................................................................ 3-6
3.5.1 Serial Port Initialization.......................................................................................... 3-6
3.5.2 Serial Console Option............................................................................................. 3-7
3.5.3 Using a Serial Printer.............................................................................................. 3-8
3.5.4 Using a Serial Modem ............................................................................................ 3-9
3.6 Using Floppy Drives ............................................................................................................. 3-10
3.6.1 Drive Parameter Setup............................................................................................ 3-10
3.6.2 Single-Floppy Configurations ................................................................................ 3-10
3.7 Using SCSI Hard Disk Drives............................................................................................... 3-11
3.7.1 Drive Parameter Setup............................................................................................ 3-11
3.7.2 Preparation for DOS Use........................................................................................ 3-12
3.8 AT Bus Controller Interfaced Hard Disk Drives .................................................................. 3-14
CHAPTER 4 - THEORY OF OPERATION
4.1 Introduction........................................................................................................................... 4-1
4.2 Overall Architecture.............................................................................................................. 4-3
4.2.1 Standard AT System Functions .............................................................................. 4-3
4.2.2 Unique Functions.................................................................................................... 4-3
4.2.3 System Memory Map ............................................................................................. 4-4
4.2.4 System I/O Map...................................................................................................... 4-5
4.3 AT Motherboard Logic ......................................................................................................... 4-6
4.3.1 CPU......................................................................................................................... 4-6
4.3.2 CPU and Bus Speed Control................................................................................... 4-6
4.3.3 ROM-BIOS Sockets ............................................................................................... 4-7
4.3.4 Onboard DRAM Memory....................................................................................... 4-7
4.3.5 Interrupt Controllers ............................................................................................... 4-8
4.3.6 DMA Controllers.................................................................................................... 4-8
4.3.7 Programmable Timers ............................................................................................ 4-10
4.3.8 Keyboard Interface ................................................................................................. 4-10
4.3.9 Speaker Interface .................................................................................................... 4-11
4.3.10 Battery-Backed Clock............................................................................................. 4-11
4.3.11 AT Expansion Bus.................................................................................................. 4-11
4.4 Floppy Disk Controller ......................................................................................................... 4-12
4.5 Serial/Parallel Controller....................................................................................................... 4-13
4.5.1 Serial Ports.............................................................................................................. 4-13
4.5.2 Parallel Printer Port................................................................................................. 4-14
4.6 Small Computer System Interface (SCSI) ............................................................................ 4-16
4.7 Byte-Wide Memory Sockets................................................................................................. 4-19
4.8 Configuration EEPROM....................................................................................................... 4-20