Atari 400

4.2 The ATARI 400 and 800 Computer Console Systems 4-1
4.2.1 Motherboard 4-1
4.2.2 Central Processing Unit 4-2
4.2.3 ROM Personality Board 4-3
4.2.4 RAM Memory pcb 4-3
4.2.5 Keyboard 4-4
4.2.6 Power Supply 4-4
4.2.7 Program Cartridge 4-4
4.3 Functional Block Diagram Discussion 4-4
4.3.1 Central Processing Unit 4-5
4.3.2 Motherboard Console System {400) 4-7
4.3.2.1 POKEY Integrated Circuit 4-8
4.3.2.2 Peripheral Interface Adapter (PIA) 4-9
4.3.2.3 KeyIn/KeyOut Integrated Circuits 4-12
4.3.2.4 Memory Map Decoder 4-12
4.3.2.5 I/O Decoder 4-13
4.3.3 Motherboard Console System (800) 4-14
4.3.3.1 Bidirectional Data Buffer 4-14
4.3.3.2 I/O Decoder 4-14
4.3.3.3 Composite Video 4-14
4.3.4 ROM Personality Board 4-14
4.3.5 RAM Memory Boards 4-16
4.3.6 Power Supply 4-16
4.3.7 Program Cartridge 4-17
CHAPTER 5 - MAINTENANCE 5-1
5.1 Introduction 5-1
5.2 Preventive Maintenance 5-1
5.2.1 PCB Contact Cleaning and Lubrication 5-2
5.2.2 Visually Inspecting the Computer Consoles 5-3
5.3 System Check-Out 5-3
5.3.1 Memo Pad Test 5-3
5.3.2 Shock Test 5-5
5.3.3 Picture Quality Test 5-5
5.3.4 Keyboard Test 5-6
5.3.5 Stand Alone Test (Diagnostic) 5-7
5.4 Troubleshooting Guide 5-18
5.4.1 Troubleshooting -- Procedure Number One 5-19
5.4.2 Troubleshooting -- Procedure Number Two 5-21
5.4.3 Troubleshooting -- Procedure Number Three 5-23
5.4.4 Integrated Circuit Replacement Procedures 5-23
5.4.5 Motherboard 5-27
5.5 Dissassembly, 400Computer Console 5-30
5.6 Disassembly, 800 Computer Console 5-33
5.7 Assembly, 400 Computer Console 5-40
5.8 Assembly, 800 Computer Console 5-43
CHAPTER 6 - SPARE PARTS LIST AND ORDERING/REPORTING INFORMATION 6-1
6.1 Introduction 6-1
6.2 Spare Parts List 6-1