Table Of Contents - NEC Advanced Personal Computer System Reference Manual

Contents
Page
PREFACE ......................................................
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CHAPTER 1 HARDWARE OVERVIEW
CHAPTER 2 PROCESSOR PCB
2.1 MOTHER BOARD/CARD CAGE INTERFACE ......... 2-3
2.2 MICROPROCESSOR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-13
2.3 DIRECT MEMORY ACCESS .......................... 2-14
2.4 INTERVAL TIMER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-19
2.5 INTERRUPT CONTROL. . . . . . . . . . . . . . . . . .. . . . . . . . . . .. 2-20
2.6 MEMORY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-26
2.6.1 Main Memory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-27
2.6.2 Battery-Backed Memory. . . . . . . . . . . . . . . . . . . . . . .. 2-28
2.6.3 Read Only Memory ............................ 2-29
2.7 PARALLEL PRINTER CONTROL ...................... 2-29
2.7.1 Interface ...................................... 2-29
2.7.2 Programming Considerations. . . . . . . . . . . . . . . . . . .. 2-29
2.8 KEYBOARD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-38
2.8.1 Keyboard Layout and Scan Codes. . . . . . . . . . . . . . .. 2-39
2.8.2 Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-41
2.9 CALENDAR AND CLOCK GENERATOR .............. 2-42
2.9.1 Circuit Description. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-43
2.9.2 Programming Considerations. . . . . . . . . . . . . . . . . . .. 2-44
2.10 JUMPER SETTINGS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-44
CHAPTER 3 CONTROLLER PCB
3.1 MOTHER BOARD/CARD CAGE INTERFACE ......... 3-1
3.2 CRT DISPLAY CONTROL ............................ 3-4
3.2.1 Display Buffer Memory. . . . . . . . . . . . . . . . . . . . . . . .. 3-5
3.2.2 Programming Considerations. . . . . . . . . . . . . . . . . . .. 3-8
3.3 CRT DISPLAY UNIT ................................. 3-18
3.4 FLEXIBLE DISK DRIVE CONTROLLER. . . . . . . . . . . . . .. 3-21
3.4.1 Programming Considerations. . . . . . . . . . . . . . . . . . .. 3-24
3.4.2 Drive A and B Interface. . . . . . . . . . . . . . . . . . . . . . . .. 3-37
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