Apple Desktop Computer manual Nmi

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A P P E N D I X A

Abbreviations

NMI

nonmaskable interrupt

NV-RAM

nonvolatile random-access memory

OHCI

Open Host Controller Interface

OS

operating system

PCI

Peripheral Component Interconnect, an industry-standard

 

expansion bus

PLL

phase-locked loop

POST

power-on self test

RAM

random-access memory

RAID

random array of inexpensive disks

RCA

Radio Corporation of America

rms

root mean square

ROM

read-only memory

RTAS

run-time abstraction services

SCC

Serial Communications Controller

SCSI

Small Computer System Interface

SDRAM

synchronous dynamic RAM

SGRAM

synchronous graphics RAM; used for display buffers

SNR

signal to noise ratio

SO-DIMM

small outline dual inline memory module

SPD

Serial Presence Detect, a feature of the SO DIMM

USB

Universal Serial Bus, an industry-standard

 

expansion bus

VCC

positive supply voltage (voltage for collectors)

VIA

versatile interface adapter

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Contents Apple iMac Computer Page Contents RAM Expansion Devices and PortsRtas SoftwareRtas NV-RAM Appendix Abbreviations IndexFigures and Tables Page About This Developer Note Contents of This NoteATA Devices PowerPC G3 MicroprocessorSupplemental Reference Documents Mac OSOpen Firmware USB DevicesE F a C E Introduction Features Shows a front view of the computer Case and External FeaturesFront view 2Side view showing I/O bay System Software Compatibility IssuesUSB Ports and Devices Main RAM Expansion ModulesVideo RAM Expansion Modules Page Architecture Architecture Backside Cache Processor moduleG3 Microprocessor Controller IC Main Logic BoardMemory Controller and PCI Bridge Built-in Modem USB ControllerVideo Display Subsystem Infrared Link Module Devices and Ports USB Ports USB ConnectorsGND Transfer Types SupportedADB Compatibility USB Compatibility IssuesUSB Controller Serial Port CompatibilityMacintosh-To-Macintosh Connections USB Storage DevicesKeyboard Layout KeyboardKeyboard and USB MouseVideo Display Hard Disk DriveSound System Infrared Communication LinkExternal Sound Input Sound InputsSound Outputs Built-in MicrophoneHeadphone Jacks Sound SpecificationsExternal Sound Output Total harmonic distortion Internal Modem Ethernet PortPage RAM Expansion Placing the Computer Face Down Removing the Logic Board AssemblyExpansion Slots Unfastening the Cables Removing the bottom coverRAM Expansion Removing the Retaining Screws 3Logic board assembly handle and retaining screwsRemoving the EMI Shield Removing the Logic Board AssemblyLocations of the Expansion Slots 6Locations of the RAM expansion slots Main RAM ExpansionElectrical Design of RAM SO-DIMMs Mechanical Design of RAM SO-DIMMsSdram Devices Configuration of RAM SO-DIMMs Address Multiplexing RAM SO-DIMM Electrical LimitsVideo RAM Expansion Page Software Why Make This Change? What Has Changed Features of the New Approach Data Structures and Files PerformanceRAM Footprint User ExperienceBoot ROM Contents Rtas Mac OS ndrv DriversToolbox Image File Contents ToolBox ROM Image NewWorld Boot ProcessTrampoline Code Interrupt Handling What Is DifferentRAM Footprint Outmoded ResourcesStartup Disk Control Panel NanoKernelMachine Identification Open Firmware and the Device TreeInterrupt Layout Software Abbreviations Chrp NMI Page Index Nvram X, Y, Z Allen Watson