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1 port 80h post code leds – Asus PRL-DLS User Manual

Page 56

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2-28

Chapter 2: Hardware information

2.9.1 Port 80h post code LEDs

8 7 6 5 4 3 2 1

FFh

C0h

0Dh

00h

LED

POST Code < C0h >

1. Chipset very early initialization.

2. Programed chipset registers before memory detection.

POST Code < C1h >

1. Power on check.

2. Memory detection and initialization.

POST Code < 80h > : Get memory type from SPD.

If BIOS can’t get SPD = Error Code < D0h >

If memory type is not DDR-SDRAM = Error Code < D8h >

POST Code < 81h > : Get size and timing information from SPD.

POST Code < 82h > : Set memory size according to each memory module.

POST Code < 83h > : Set memory timing.

POST Code < 84h > : Initialize memory module.

POST Code < 85h > : Do DQS for memory module.

POST Code < 86h > : Finish memory detection and initialization

3. Test first 256 MB memory.

POST Code < 0Ch >

1. BIOS checksum verify.

POST Code < C3h >

1. Decompressed BIOS codes into memory.

POST Code < C5h >

1. Shadow system BIOS.