Option ROM,
Continued
Byte
Name
Description
07h
ROM part
length
Indicates the length of each byte
address in the set. It is the number of
bytes associated with each byte in the
ROM in Kbytes.
NOTE
The number of bytes in the ROM set
equals the sum of the number of bytes
in each of the ROM parts divided by
the data path of each device. Each
of the ROM parts on the option board
must have the same number of bytes.
8
Reserved
Reserved for ROM set data.
Last
byte
Checksum
Each byte in the ROM set has a simple
add and rotate checksum in its last
byte.
Option ROM
Set Format
For options that have a one-byte or two-byte data path, the data
from the ROM set must be moved into RAM. Note that a device
cannot have both an 8-bit data path and a 16-bit data path. An
option with a full 32-bit data path may not have to be moved.
Devices with a 16-bit data path are treated as though each byte of
the device is a device in itself.
Figure 2–4 shows option ROM set data.
Figure 2–4 Option ROM Set Data
Option Revision Number
Option Index Value
Reserved for Expansion (32 bytes)
Device Configuration Table (DCT) Template
31
00
LJ-00102-TI0
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