The Power On Self Test :: essays research papers

The provide On Self TestWhen the system is powered on, the BIOS will practice diagnostics and initializesystem components, including the video system. (This is self-evident when thescreen foremost flicks before the Video Card header is displayed). This is commonlyreferred as come out (Power-On Self Test).Afterwards, the computer will proceed its final boot-up stage by calling theoperating system. Just before that, the user may interrupt to welcome access toSETUP.To will the user to alter the CMOS settings, the BIOS provides a half-size program,SETUP. Usually, setup can be entered by mechanical press a redundant key combination (DEL,ESC, CTRL-ESC, or CRTL-ALT-ESC) at boot time (Some BIOSes allow you to entersetup at any time by pressing CTRL-ALT-ESC). The AMI BIOS is mostly entered bypressing the DEL key after resetting (CTRL-ALT-DEL) or powering up the computer.You can bypass the extended CMOS settings by holding the key pot duringboot-up. This is really helpful, especia lly if you bend the CMOS settings rightout of shape and the computer wont boot properly anymore. This is also a handytip for race who play with the older AMI BIOSes with the XCMOS setup. Itallows changes directly to the chip registers with very little goodexplanation.A Typical BIOS POST SequenceMost BIOS POST sequences travel by along four stages1. let on some basic information or so the video card like its brand,video BIOS version and video retrospection available.2.Display the BIOS version and copyright notice in upper mettle screen.You will see a large sequence of pieces at the bottom of the screen. Thissequence is the .3.Display memory count. You will also visit tick sounds if you have enabledit (see Memory Test Tick Sound section).4. at one time the POST have succeeded and the BIOS is ready to call the operatingsystem (DOS, OS/2, NT, WIN95, etc.) you will see a basic table of the systemsconfigurationsMain processor The type of CPU identified by the BIOS. Usually Cx386D X,Cx486DX, etc..Numeric central processing unit Present if you have a FPU or None on the contrary. Ifyou have a FPU and the BIOS does not recognize it, see section Numeric mainframeTest in Advanced CMOS Setup.Floppy Drive A The require A type. See section Floppy drive A in warningCMOS Setup to alter this setting.Floppy Drive B Idem.Display Type See section Primary display in Standard CMOS Setup.AMI or Award BIOS Date The revision date of your BIOS. Useful to take note when you have compatibility problems with adaptor cards (notably fancyones).Base Memory surface The number of KB of base memory. Usually 640.Ext. Memory Size The number of KB of extended memory.