Acer Altos R310 Service Manual

Also see for Altos R310: User guide User guide User guide

Contents

Acer Altos R310 Service Manual Manual pdf 59 page image

53 Altos R310BIOS POST Checkpoint CodesThe POST code checkpoints are references and instructions used duing the BIOS pre-boot process.The following table describles the checkpoints and associated beep codes, if any, that may occur duringthe POST portion of the BIOS.Checkpoint Code Beep Code Description01h One short beepbefore boot02h Verify Real Mode. If the CPU is in protected mode,turn on A20 and pulse the reset line, forcing ashutdown 0.NOTE: Hook routine should not alter DX, whichholds the powerup CPUID.03h Disable Non-Makable Interrupts (NMI).04h Get CPU type from CPU registers and othermethods.Save CPU type in NVRAM.NOTE: Hook routine should not alter DX, whichholds the powerup CPUID.06h Initialize system hardware. Reset the DMAcontrollers, disable video, clear any pendinginterrupts from the real-time clock and setup port Bregister.07h Disable system ROM shadow and start to executeROMEXEC code from the flash part. This taks ispulled into the build only when the ROMEXECrelocatoin is installed.08h Initialize chipset registers to the lnitial POST Values.09h Set in-POST flag in CMOS that indicates we are inPOST. If this bit is not cleared by post -ClearBootFlag(AEh), the BIOS no next bootdetermines that the current configuration causedPOST to fail and uses default values forconfiguration.Clear the CMOS diagnostic byte (register E). Checkthe real-time clock and verify the battery has not lostpower. Checksum the CMOS and verify it has notbeen corrupted.0Ah Initialize CPU registers.0Bh Enable CPU cache. Set bits in CMOS related tocache.0Ch Set the initial POST values of the cache registers ifnot integrated into the chipset.0Eh Set the initial POST values of registers in theintegrated I/O chip.0Fh Enable the local bus IDE as primary or secondarydepending on other drives detected.10h Initialize power management11h General dispatcher for alternate register initialization.Set initial POST values for other hardward devicesdefined in the register tables.