User guide

B-4 Sun Fire X2100 Server User Guide April 2007
POST Code Description
25h Early PCI initialization:
Enumerate PCI bus number.
Assign memory and I/O resource.
Search for a valid VGA device and VGA BIOS, and put it into C000:0.
26h 1. If Early_Init_Onboard_Generator is not defined Onboard clock generator
initialization. Disable respective clock resource to empty PCI and DIMM
slots.
2. Init onboard PWM.
3. Init onboard H/W monitor devices.
27h Initialize INT 09 buffer.
28h Reserved.
29h 1. Program CPU internal MTRR (P6 and PII) for 0-640K memory address.
2. Initialize the APIC for Pentium class CPU.
3. Program early chipset according to CMOS setup. Example: onboard IDE
controller.
4. Measure CPU speed.
2Ah Reserved.
2Bh Invoke video BIOS.
2Ch Reserved.
2Dh 1. Initialize double-byte language font (optional).
2. Put information on screen display, including award title, CPU type, CPU
speed, full-screen logo.
2Eh Reserved.
2Fh Reserved.
30h Reserved.
31h Reserved.
32h Reserved.
33h Reset keyboard if Early_Reset_KB is defined- for example, Winbond 977
series Super I/O chips. See also POST 63h.
34h Reserved.
35h Test DMA Channel 0.
36h Reserved.
37h Test DMA Channel 1.
TABLE B-1 BIOS Port 80 POST Codes (Continued)