文档介绍：OperatingSystems软件学院高海昌******@xidian.* ** ******* ** ***** *** **** * ***Chapter5:Input//OsoftwareI/.-*OScontrolI/OdeviceMainfunctions:mandstothedevicesCatchinterruptsHandleerrorsProvideaninterfacebetweenthedevicesandtherestofthesystemthatissimpleandeasytouseDeviceindependence*PrinciplesofI/OHardwareBlockdeviceStoresinformationinfixed-sizeblocks,,,mouseOtherdeviceclock*PrinciplesofI/work,anddatabaserates*DeviceControllersI/ponents:ponent(device)ponentisthedevicecontrollermaybeabletohandlemultipledevicesController'stasksConverttheserialbitstreamintoablockofbytesPerformanyerrorcorrectionnecessaryCopyittomainmemory*Memory-MappedI/:mandthedevicetodeliverdata,acceptdata,switchitselfonoroff,:OScanlearnwhatthedevice’sstateis,mand,,manydeviceshaveadatabufferthattheOScanreadandwrite().Q:municateswiththecontrolregistersandthedevicedatabuffer?*Memory-MappedI/O(2)(a)SeparateI/Oandmemoryspace(IBM360)EachcontrolregisterisassignedanI/(b)Memory-mappedI/O(PDP-11).(c)Hybrid(Pentium)Memory-mappedI/Odatabuffers,separateI/Oportsforthecontrolregisters.*Memory-MappedI/OAdvantagesWithmemory-