Apple Desktop Computer manual

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Technical Publications

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Developer Note

Apple iMac Computer

Developer Note

Contents

Main Page Contents Architecture Chapter 2 Introduction Devices and Ports RAM Expansion Software Page Chapter 4 Chapter 3 RAM Expansion Devices and Ports Page About This Developer Note Contents of This Note 0 Supplemental Reference Documents 0 ATA Devices 0 Mac OS 0 PowerPC G3 Microprocessor 0 USB Devices 0 Open Firmware 0 Page Page Features 1 Case and External Features 1 Page Page Compatibility Issues 1 System Software 1 Main RAM Expansion Modules 1 USB Ports and Devices 1 Video RAM Expansion Modules 1 Page Page Architecture Figure 2-1 Block diagram Processor module 2 G3 Microprocessor 2 Backside Cache 2 Memory Controller and PCI Bridge 2 Main Logic Board 2 I/O Controller IC 2 USB Controller 2 Video Display Subsystem 2 Built-in Modem 2 Page Page USB Ports 3 USB Connectors 3 Transfer Types Supported 3 USB Compatibility Issues 3 ADB Compatibility 3 Serial Port Compatibility 3 Macintosh-To-Macintosh Connections 3 USB Storage Devices 3 USB Controller 3 CHAPTER 3 Keyboard 3 Keyboard Layout 3 Figure 3-2 ANSI keyboard layout Keyboard and USB 3 Mouse 3 Hard Disk Drive 3 Video Display 3 Infrared Communication Link 3 Sound System 3 Sound Inputs 3 Built-in Microphone 3 External Sound Input 3 Sound Outputs 3 Internal Speakers 3 Sound Specications 3 Page Ethernet Port 3 Internal Modem 3 Page Page The Expansion Slots 4 Removing the Logic Board Assembly 4 Placing the Computer Face Down 4 Removing the bottom cover 4 Unfastening the Cables 4 Page Removing the Retaining Screws 4 Removing the Logic Board Assembly 4 Removing the EMI Shield 4 Locations of the Expansion Slots 4 Main RAM Expansion 4 Mechanical Design of RAM SO-DIMMs 4 Electrical Design of RAM SO-DIMMs 4 SDRAM Devices 4 Conguration of RAM SO-DIMMs 4 Address Multiplexing 4 RAM SO-DIMM Electrical Limits 4 Video RAM Expansion 4 Page Page Why Make This Change? 5 What Has Changed 5 Features of the New Approach 5 Performance 5 RAM Footprint 5 User Experience 5 Data Structures and Files 5 Compatibility 5 Boot ROM Contents 5 POST Code 5 Open Firmware 5 Mac OS 'ndrv' Drivers 5 RTAS 5 Toolbox Image File Contents 5 Open Firmware Script 5 Trampoline Code 5 ToolBox ROM Image 5 NewWorld Boot Process 5 What Is Different 5 Interrupt Handling 5 Outmoded Resources 5 RAM Footprint 5 RTAS 5 NV-RAM 5 NanoKernel 5 Startup Disk Control Panel 5 Open Firmware and the Device Tree 5 Interrupt Layout 5 Machine Identication 5 Page Abbreviations A Page Page Page Index K L M N O S T U V, W, X, Y, Z