NCR RealPOS 40 - Power Management; G3 Mechanical off; G2;S5 Soft off; G1 Sleeping

Chapter 1: Product Overview 1-13
Power Management
TheBIOSsupportstheAdvancedConfigurationandPowerManagementInterface
(ACPI)2.0specification.AkeyfeatureofACPIisthattheoperatingsystem,notthe
BIOS,configuresandimplementspowermanagement.The7600terminalsupports
theGlobalsystempowerstatesdefinedbyACPI:
G3 Mechanical Off
Acomputerstatethatisenteredandleftbyamechanicalmeans
Example: Turningoffthesystem’spowerthroughthemovementofalargered
switch.
Variousgovernmentagenciesandcountriesrequirethisoperatingmode.Itisimplied
bytheentryofthisoffstatethroughamechanicalmeansthatnoelectricalcur
rentis
runningthroughthecircuitryandthatitcanbeworkedonwithoutdamagingthe
hardwareorendangeringservicepersonnel.TheOSmustberestartedtoreturntothe
Workingstate.Nohardwarecontextisretained.Exceptforthereal‐timeclock,power
consumptioniszero.
G2/S5 Soft Off
Acomputerstatewherethecomputerconsumesaminimalamountofpower.Nouser
modeorsystemmodecodeisrun.Thisstaterequiresalargelatencyinordertoreturn
totheWorkingstate.Thesystem’scontextwillnotbepreservedbythehardware.The
systemmustberestartedtoreturntotheWorkingstate
.Itisnotsafetodisassemble
themachineinthisstate.
G1 Sleeping
Acomputerstatewherethecomputerconsumesasmallamountofpower,usermode
threadsarenotbeingexecuted,andthesystemappearstobeoff(fromanenduser’s
perspective,thedisplayisoff,andsoon).LatencyforreturningtotheWorkingstate
variesonthewakeenvironmentselectedpriortoentryofthisstate(forexample,
whetherth
esystemshouldanswerphonecalls).Workcanberesumedwithout
rebootingtheOSbecauselargeelementsofsystemcontextaresavedbythehardware
andtherestbysystemsoftware.Itisnotsafetodisassemblethemachineinthisstate.
G0 Working
Acomputerstatewherethesystemdispatchesusermode(application)threadsand
theyexecute.Inthisstate,peripheraldevices(peripherals)arehavingtheirpower
statechangeddynamically.Theusercanselect,throughsomeUI,various
performance/powercharacteristicsofthesystemtohavethesoftwareoptimizefor
performanceorbatterylife.Thesyst
emrespondstoexternaleventsinrealtime.Itis
notsafetodisassemblethemachineinthisstate.