Option ROM,
Continued
Byte
Name
Description
00h
Data path
indicator
Indicates the size of the ROM data
path. The data path must be one of the
following:
1: One byte per longword. Bytes
in ROM occupy the low byte of
each longword.
2: Two bytes per longword. Words
in ROM occupy the low two bytes
of each longword.
4: Four bytes per longword.
Longwords in ROM correspond
to longwords in the address space.
02h
Version
Contains the low 8 bits of the version
number for the option firmware.
03h
ROM Byte
number
Indicates the position of the byte
among the set of ROMs used to
implement the firmware. This value is
equal to the low 2 bits of the physical
address of the first byte in the ROM
set. Note that this value is always less
than the data path indicator.
04h to
06h
Manufacturing
check data
Performs quick verify check of the
ROM contents. The data are 55h, AAh,
and 33h.
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