INDEX

+5V DC	43,45,47,49,51,52
-5V DC	49,51,52,182
+12V DC	47,49,51,52,182
-12V DC	49,51,52,182

6845 CRTC Emulation	33

Alpha Display	25
Alpha/Graphics Colour VDU Controller	24
Alpha Mode Character Generator ROM	37
Asynchronous Communications Element (8250) Registers (table)	120
Asynchronous Communications Element test	60
Attribute Byte	25, 76

Bootstrap	57, 98
Break	68, 102
BREAK Command	164
BUFFERS Command	164
Bus Cycle	7
Calendar - Time, Calendar and Alarm Locations	131
Caps Lock	68, 95, 107
Character Generator ROM - Alpha Mode	37
Character Set - ROM	183
Checksum	54, 59, 90, 112, 114
Clock - Real time	21
Clock Frequency	7
Colour Planes	27,28,92
Colours	24
Command - BREAK - BUFFERS - Country - DEVICE - DRIVPARM - FCBS - FILES - LASTDRIVE - SHELL	164 164 165 165 167 168 168 168 169
Connector	43, 45, 46, 51, 52
Control Register - VDU Mode	28
Controller - Floppy Disk Controller (uPD765A) Registers - High Performance Programmable DMA Controller Registers - Programmable Interrupt Controller Command Words	136 124 126
Conversion to 640K	183
Counter 1 Initialisation	16
COUNTRY Command	165
Country Dependent Information for MS-DOS 3.2	170
CPU	7
CRTC Display Addressing	35
CRTC (MC6845) Emulation	33, 34
Crystal Oscillator	21
Cursor	34, 72
Cursor Off	35

Divide by Zero	55
DEVICE Command	165
Device Driver - DEVICE Command - DRIVER.SYS - RAMDRIVE.SYS	165 166 166
Direct Memory Access see DMA	11
Direct Memory Access Controller Test	60
Disk I/O	82
Disk Parameter Table	104
Disk test	61
Display - Alpha - Graphics	25 26
Display RAM Access Overhead	36
Display RAM Mapping	36
DMA	11
DMA Controller - High Performance DMA Controller (8237A-4) Registers	54 124
DMA Initialisation	13
DMA Page Registers	12
DRIVER.SYS	166
DRIVPARM Command	167

Enhanced Function Interrupt	89
Error: Faulty - direct memory access controller - floppy disk controller or disk drive - interrupt controller - interval timer - real time clock - ROS ROM checksum - memory (parity error) - mouse coordinate register - SYSTEM RAM - system printer port - system serial port - system status register - VDU controller - VDU RAM	113,114
Expansion Bus	7, 48
Expansion Bus I/O Channels	11
Expansion Card Interface	48
External Ticker Interrupt	103

Fatal ROS Messages	114
FCBS Command	168
FDC Hardware Conditions	38
FILES Command	168
Firmware	53
Floppy Disk Controller - Hardware Conditions - Interrupt 14: - Registers (uPD765A)	38 38 70 136
Format Track	85

Graphics Display	26
Graphics Mode 1	26 7 1
Graphics Mode 2	26 7 2
Graphics Mode 2 Border Register	32, 92

Initialisation Counter 1 DMA Interrupt Controller Power Up and Self Test	16 13 15 53
Interfaces Mouse Software	18
Input/Keyboard Code Status-1 - Port A	18
Interrupt 2: Parity Error (NMI)	62
Interrupt 5: Print Screen	62
Interrupt 6: Mouse Button Control	63
Interrupt 8: System Clock Interrupt	63
Interrupt 9: Keyboard Interrupt	64
Interrupt 14: Floppy Disk Controller	70
Interrupt 16: VDU I/O VDU Control Registers VDU Controller - Alph/Graphics Colour VDU Colour Plane Read Register VDU Colour Plane Write Register VDU Colour Select Register VDU Graphics Mode 2 Border Register VDU Mode Control Register VDU RAM and VDU Controller test VDU Status Register VDU Sub-Function 0: Set VDU Mode VDU Sub-Function 1: Set Cursor Size VDU Sub-Function 2: Set Cursor Address VDU Sub-Function 3: Get Cursor Address VDU Sub-Function 4: Get Light Pen Address VDU Sub-Function 5: Set Display Page VDU Sub-Function 6: Scroll Screen UP VDU Sub-Function 7: Scroll Screen Down VDU Sub-Function 8: Read Character and Attributes VDU Sub-Function 9: Write Character Attributes VDU Sub-Function 10: Write Character only VDU Sub-Function 11: Write Colour Select Register VDU Sub-Function 12: Write a Pixel VDU Sub-Function 13: Read a Pixel VDU Sub-Function 14: Write in TTY Emulation Mode VDU Sub-Function 15: Get Current VDU Parameters	70 28 24 31 30 29 32 28 59 33 71 72 73 73 73 74 74 75 76 76 77 78 78 79 79 80
Interrupt 17: System Configuration	80
Interrupt 18: Memory Size	81
Interrupt 19: Disk I/O Disk Sub-Function 0: Initialise Disk Sub-System Disk Sub-Function 1: Return Last Status Disk Sub-Function 2: Read Sector Disk Sub-Function 3: Write Sector Disk Sub-Function 4: Verify Sector Disk Sub-Function 5: Format Track	82 82 83 83 84 84 85
Interrupt 20: Serial I/O Serial Sub-Function 0: Initialise Port Serial Sub-Function 1: Send Character Serial Sub-Function 2: Read Character Serial Sub-Function 3: Get Channel Status	86 87 88 89 89
Interrupt 21: Enhanced Function Interrupt Enhanced Sub-Function 0: Read/Reset Mouse X/Y Counts Enhanced Sub-Function 1: Write NVR Location Enhanced Sub-Function 2: Read NVR Location Enhanced Sub-Function 3: Write VDU Colour Plane Write Register Enhanced Sub-Function 4: Write Colour Plane Read Register Enhanced Sub-Function 5: Write VDU Graphics Border Register Enhanced Sub-Function 6: Return ROS Version Number	89 90 90 91 92 92 92 93
Interrupt 22: Keyboard I/O Keyboard Sub-Function 0: Get Key Token Keyboard Sub-Function 1: Return Keyboard Buffer Status Keyboard Sub-Function 2: Return Shift States	93 94 94 94
Interrupt 23: Printer I/O Printer Sub-Function 0: Print Character Printer Sub-Function 1: Initialise printer channel Printer Sub-Function 2: Return Channel Status	96 97 97 97
Interrupt 24: System Restart	98
Interrupt 25: Disk Bootstrap	98
Interrupt 26: System Clock & Real Time Clock Clock Sub-Function 0: Get System Clock Clock Sub-Function 1: Set System Clock Clock Sub-Function 2: Get RTC Time Clock Sub-Function 3: Set RTC Time Clock Sub-Function 4: Get RTC Date Clock Sub-Function 5: Set RTC Date Clock Sub-Function 6: Set RTC Alarm Clock Sub-Function 7: Kill RTC Alarm	98 99 99 99 100 101 101 102 102
Interrupt 27: Keyboard Break Interrupt	102
Interrupt 28: External Ticker Interrupt	103
Interrupt 29: VDU Parameter Table	103
Interrupt 30: Disk Parameter Table	104
Interrupt 31: VDU Matrix Table	105
Interrupt Controller - Initialisation - Programmable Interrupt Controller Command Words	57 13 126
Interrupt Levels	14
Interrupts	13, 14, 55
Interval Timer - Programmable Interval Timer (8253) Registers	130
Interval Timers	15
I/O Channels - Main Board - Expansion Bus	7 9 11

Joystick Interface	45
Joystick Connector	46

Key Actions - Special	68
Key Codes	18,43,94,108
Keyboard	57,93,94
Keyboard Keycodes	185
Keyboard Interrupt - Interrupt 9	43
Keyboard Interface	42
Keyboard Interface test	61
Keyboard Layouts Danish French German Italian Swedish UK USA	186 189 187 187 188 189 186 186
Keyboard to Main Board Interface see also Main Board to Keyboard Interface	42 43
KEYBUK Command	169
Keycodes	43, 64, 118 - 120, 185

Language Links	23, 116
LASTDRIVE Command	168
Light Pen Connector	46
Links	23, 37, 116, 183
Luminance	24

Main Board I/O Channels	9
Main to Keyboard Interface	43
MC6845 CRTC Emulation	33
Memory Layout	7
Memory Size	8, 81, 107
Mode 1 - Graphics	26, 71
Mode 2 - Graphics	26, 71
Mode Mapping Relationships	36
Monochrome Grey Scales	25
Mouse Button Control - Interrupt 6	63
Mouse Connector	44
Mouse Registers	9, 90
Mouse Software Interfaces	153
MS-DOS 3.2 Country Dependent Information for	170
MS-DOS System Configuration	164
Mouse Interface	44
Mouse X and Y Count Register test	61

NMI Mask Control	15, 57
Non-Fatal ROS Messages	113
Non-Volatile RAM	112
Numeric Data Co-processor	7
Num Lock	68, 95, 107

NVR	21, 54, 90
On-Board RAM	8, 183
OUT0, OUT1, OUT2	16

Parallel Printer Port - Interface	22 41
Parity Error	55, 62
Page Registers	12, 13
Pin Arrangement - Serial Channel - Parallel printer port	40 41
Pixel to RAM assignment	27, 28
Port A - Status-1 Input/Keyboard Code	18
Port B - System Control	17
Port C - Status-2 Input	19
Power Connector	52
Power Sense	21
Power Supply Requirements	182
Power-Up Initialisation and Self Test	53
Power-Up Self Tests	58
Print Screen - Interrupt 5	62,68
Printer Control Latch	22
Printer Data Latch	22
Printer I/O	96
Printer Lead (PL-2) Wiring Specification	180
Printer parallel Port test	61
Printer Port - Parallel	22
Printer Status Channel	23, 96
Processor Memory Usage	8, 116
Programmable Interrupt Controller test	61
Programmable Interval Timer test	60
Programmable Interval Timers	15
Programmable Peripheral Interface test	60

RAM0 to RAM4	19
RAM Variables	105
RAM - Non-Volatile	112
RAMDRIVE.SYS	166
RDSEL Bits	31, 32, 92
Real Time Clock	21, 98
Real Time Clock (HD146818) Registers	131
Real Time Clock test	60
Register - VDU Colour Select - VDU Colour Plane Write - VDU Colour Plane Read - VDU Display Modes/Mode Mapping Relationship - VDU Graphics Mode 2 Border - VDU RAM Access Overhead - VDU Status	29 30 31 36 32 36 33
Reset	68
Resident Operating Systems - see also (ROS)	7, 57, 93
ROM	7, 57
ROM Character Set	183
ROS Checksum Test	59
ROS Interrupts	62
ROS Messages - Fatal - Non-Fatal	113 114 113
RS232C Asynchronouse Serial Port - Asynchronous Communications Element Registers (table) - Asynchronous Communications test - Connections - Hardware Flow Control	39 120 60 171 175
RTC Alarm	102
RTC Register Locations	133

Scroll Lock	68, 95, 107, 108
Self Test	58
Serial Channel Interface	39
Serial Channel Pin Arrangement	40
Serial Clock and Serial Data	42
Serial I/O	39, 40, 86
Serial Port - RS232C Asynchronous	39
Serial Port - Asynchronous Communications Element Test	60
SHELL Command	169
Single Step	55
Speaker	15, 16
Special Key Actions	68
Stars-and-Bars	36
Status-1 Input/keyboard Code - Port A	18
Status-2 Input - Port C	19
System Control - Port B	19
System Clock	98, 99
System Clock Interrupt - Interrupt 8	63
System Configuration - MS-DOS	164
System Interrupts	13
System RAM	7
System RAM test	61
System Reset	21
System Status-1 - Write	20
System Status-2 - Write	20
System Status and Control	16, 80

Test Methods - self tests	59
Test Procedure - self tests	58
Time, Calendar and Alarm Locations	131
Timer Configuration	16
Toggle Bit	33
TTY Emulation	79

User Area RAM test	61

VDU Colour Plane Read Register	31, 92
VDU Colour Plane Write Register	31, 92
VDU Colour Plane Select Register	30, 31
VDU Colour Select Register	29, 78
VDU Controller	24, 59
VDU I/O	70
VDU Matrix table	105
VDU Mode Control	28, 29, 71
VDU Parameter Table	103
VDU RAM	8, 26, 28, 30, 36, 59
VDU Status Register	33
Video Connector	51
VRT	21, 135

Wait States	7
Write System Status-1	20
Write System Status-2	20

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