2.7 Onboard Status Display

2.7.1 POST Code Displayer

This is an LED device to display the “POST” Code, the acronym of Power On Self Test. The computer will execute the POST action whenever you power on the computer. The POST process is controlled by the BIOS. It is used to detect the status of the computer’s main components and peripherals. Each POST Code corresponds to different checkpoints that are also defined by the BIOS in advance. For example, “memory presence test” is an important checkpoint and its POST Code is “C1”. When the BIOS execute any POST item, it will write the corresponding POST Code into the address 80h. If the POST passes, the BIOS will process the next POST item and write the next POST Code into the address 80h. If the POST fails, we can check the POST Code in address 80h to find out where the problem lies.

This LED device also displays the “POST” Code of AC2005, an “uGuru” chipset developed exclusively by ABIT computer.

The decimal point lights up during the AC2005 POST action.

See Appendix for both AWARD and AC2005 POST Code definitions.

Hardware Setup

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Abit AN9 32X manual Onboard Status Display, Post Code Displayer