Intro Index Section 1

Table of Contents:

Section 1 - Hardware

1.0Introduction
1.1CPU
1.2Memory Layout
1.3Main Board I/O Channels
1.4Expansion Bus I/O Channels
1.5DMA
1.5.1DMA Page Registers
1.5.2DMA Initialisation
1.6System Interrupts
1.6.1Interrupt Levels
1.6.2Interrupt Controller initialisation
1.6.3NMI Mask Control
1.7Programmable Interval Timers
1.7.1Timer Configuration
1.8System Status and Control
1.8.1Port B - System Control
1.8.2Port A - Status-1 Input/Keyboard Code
1.8.3Port C - Status-2 Input
1.8.4Write System Status-1
1.8.5Write System Status-2
1.8.6System Reset
1.9Real Time Clock
1.10Parallel Printer Port
1.10.1Printer Data Latch
1.10.2Printer Status Channel
1.10.3Printer Control Latch
1.11Alpha/Graphics Colour VDU Controller
1.11.1Alpha Display
1.11.2Graphics Display
1.11.2.1Graphics Mode 1
1.11.2.2Graphics Mode 2
1.11.3VDU Control Registers
1.11.3.1VDU Mode Control Register
1.11.3.2VDU Mode Select Register
1.11.3.3VDU Colour Plane Write Register
1.11.3.4VDU Colour Plane Read Register
1.11.3.5VDU Graphics Mode 2 Border Register
1.11.4VDU Status Register
1.11.5MC6845 CRTC Emulation
1.11.6CRTC Display Addressing
1.11.6.1Mode Mapping Relationships
1.11.6.2Display RAM Access Overhead
1.11.6.3Alpha Mode Character Generator ROM
1.12Floppy Disk Controller
1.12.1FDC Hardware Conditions
1.13RS232C Asynchronous Serial Port
1.13.1Serial Channel Interface
1.13.2Serial Channel Pin Arrangement
1.14Printer Parallel Port
1.15Keyboard Interface
1.15.1Serial Clock and Serial Data
1.15.2Keyboard to Main Board Interface
1.15.3Main Board to Keyboard Interface
1.15.4Keycodes
1.15.5Keyboard Connector
1.16Mouse Interface
1.16.1Mouse Connector
1.17Joystick Interface
1.17.1Joystick Connector
1.18Light Pen Connector
1.19Expansion Card Interface
1.20Video Connector
1.21Power Connector

Section 2 - Firmware

2.0Introduction
2.1Power-Up Initialisation and Self Test
2.2Power-Up Self Tests
2.2.1Test Procedure
2.2.2Test Methods
2.2.3ROS Checksum Test
2.2.4VDU RAM and VDU Controller Test
2.2.5Direct Memory Access Controller Test
2.2.6Programmable Interval Timer Test
2.2.7Programmable Peripheral Interface Test
2.2.8Real Time Clock Test
2.2.9Asynchronous Communications Element Test
2.2.10Printer Parallel Port Test
2.2.11Mouse X and Y Count Register Test
2.2.12System RAM Test
2.2.13Programmable Interrupt Controller Test
2.2.14Disk Test
2.2.15Keyboard Interface Test
2.3ROS Interrupts
2.3.1Interrupt 2: Parity Error (NMI)
2.3.2Interrupt 5: Print Screen
2.3.3Interrupt 6: Mouse Button Control
2.3.4Interrupt 8: System Clock Interrupt
2.3.5Interrupt 9: Keyboard Interrupt
2.3.5.1Special Key Actions
2.3.6Interrupt 14: Floppy Disk Controller
2.3.7Interrupt 16: VDU I/O
2.3.8Interrupt 17: System Configuration
2.3.9Interrupt 18: Memory Size
2.3.10Interrupt 19: Disk I/O
2.3.11Interrupt 20: Serial I/O
2.3.12Interrupt 21: Enhanced Function Interrupt
2.3.13Interrupt 22: Keyboard I/O
2.3.14Interrupt 23: Printer I/O
2.3.15Interrupt 24: System Restart
2.3.16Interrupt 25: Disk Bootstrap
2.3.17Interrupt 26: System Clock & Real Time Clock
2.3.18Interrupt 27: Keyboard Break Interrupt
2.3.19Interrupt 28: External Ticker Interrupt
2.3.20Interrupt 29: VDU Parameter Table
2.3.21Interrupt 30: Disk Parameter Table
2.3.22Interrupt 31: VDU Matrix Table
2.4RAM Variables
2.5Non-Volatime RAM
2.6ROS Messages
2.6.1Non-Fatal ROS Messages
2.6.2Fatal Messages

Section 3 - Tables

3.1Language Links
3.2Processor Memory Usage
3.3Keyboard and Key Codes
3.4Asynchronous Communications Element (8250) Registers
3.5High Performance DMA Controller (8237A-4) Registers
3.6Programmable Interrupt Controller (8259-A) Command Words
3.7Programmable Interval Timer (8253) Registers
3.8Real Time Clock (HD146818) Registers
3.8.1Time Calendar & Alarm Locations
3.8.2RTC Register Locations
3.9Floppy Disk Controller (uPD765A)

Appendices

1Mouse Software Interfaces
2MS-DOS System Configuration
2.1BREAK Command
2.2BUFFERS Command
2.3COUNTRY Command
2.4DEVICE Command
2.5DRIVPARM Command
2.6FCBS Command
2.7FILES Command
2.8LASTDRIVE Command
2.9SHELL Command
2.10KEYBUK Command
3Country Dependent Information for MS-DOS 3.2
4RS232C Connections
5Printer Lead (PL-2) Wiring Specification
6Power Supply Requirements
7ROM Character Set
8Keyboard Keycodes
9Keyboard Layouts
9.1UK Keyboard
9.2US Keyboard
9.3French Keyboard
9.4German Keyboard
9.5Spanish Keyboard
9.6Italian Keyboard
9.7Danish Keyboard
9.8Swedish Keyboard
Intro Index Section 1