PnP OptionROM Header

[PnP OptionROM Header]
Offset  Size       Value     Description

0x00     Byte        0x55       Signature byte 1.

0x01     Byte        0xAA      Signature byte 2.

0x02     Byte        Varies    Option ROM length in 512byte Blocks.

0x03     4Bytes    Varies    Initialization entry point(BIOS進入點).

0x07     17Bytes  Varies   Reserved(保留).

0x18     2Bytes    Varies   Offset to PCI data structure.

0x1A    2Bytes     Varies   Offset to expansion header structure.

[PCI Data Structure]

Offset  Size       Value     Description

0x00     Byte        ?             Signature byte 1.

0x01     Byte        ?             Signature byte 2.

0x02     Byte        ?             Signature byte 3.

0x03     Byte        ?             Signature byte 4.

0x04     2Bytes    Varies     Vendor Identification(廠商識別碼).

0x06     2Bytes    Varies     Device Identification(裝置識別碼).

0x08     2Bytes    Varies     Pointer to Vital Product Data().

0x0A    2Bytes    Varies     PCI Data Structure Length(PCI資料結構長度)..

0x0C    Bytec      Varies     PCI Data Structure Revision(PCI資料結構修訂版).

0x0D    3Bytes    Varies     Class Code(分類碼).

0x10     2Bytes    Varies     Image Length(影像長度).

0x12     2Bytes    Varies     Revision Level of Code/Data(程式碼/資料的修訂層級).

0x14     Byte       Varies     Code Class程式碼的型態.

0x15     Byte       Varies     Indicator(指標).

0x16     2Bytes                  Reserved(保留).          

[Code Type]  The Code Type field is a one-byte field that identifies the type of  code contained in this section of the ROM.  The code may be executable binary for a specific processor and system architecture or interpretive code.  The following code types are assigned:
Type     Description
0   Intel x86, PC-AT compatible
1   Open Firmware standard for PCI 7
2   Hewlett-Packard PA RISC
3   Extensible Firmware Interface (EFI)
4-FF       Reserved


[Last Image Indicator]  Bit 7 in this field tells whether or not this is the last image in the ROM.  A value of 1 indicates “last image;” a value of 0 indicates that another image follows.  Bits 0-6 are reserved.

[PnP Expansion Header]

Offset  Size       Value     Description

0x00     Byte        ?             Signature byte 1.

0x01     Byte        ?             Signature byte 2.

0x02     Byte        ?             Signature byte 3.

0x03     Byte        ?             Signature byte 4.

0x04     Byte        0x01       Structure revision(結構修訂版).

0x05     Byte        Varies     Length(in 16 byte increment)(以16Byte為單位基準值).

0x06     2Bytes     Varies     Offset of next header(下一個標頭偏移植).

0x08     Byte        Varies     Offset of next header(下一個標頭偏移植).

0x09     Byte        Varies     Check sum(檢查碼)

0x0A    4Bytes     Varies     Device identifier(裝置識別).

0x0E    2Bytes     Varies     Point to manufacturer string(Optional)(廠商字串指標).

0x10    2Bytes     Varies     Point to product name string(Optional)(產品名稱字串指標).

0x12    3Bytes     Varies     Device type code(裝置型態碼).

0x15    Byte         Varies     Device indicators(裝置表指標)

0x16     2Bytes     Varies     Boot Connection Vector(BCV), 0x0000 if none(開機鏈結向量, 0x0000:無). 

0x18     2Bytes     Varies     Disconnection Vector(DV), 0x0000 if none(分離向量, 0x0000:無).

0x1A    2Bytes     Varies   Bootstrap Entry Vector(BEV), 0x0000 if none(啟動程式登入向量, 0x0000:無 )

0x1C    2Bytes     0x0000   Reserved(保留).

0x1E    2Bytes     Varies     Static resource information vector(靜態資源資訊向量).