Option ROM
Overview
Each option in the Model 90 system has its own ROM firmware.
The ROM memory on the option board may be implemented as
discussed in the following sections.
Option ROM
Part Format
The option ROM part format is provided for each byte in the ROM
set. This format is compatible with the system ROM format, with
the addition of the data path indicator. Figure 2–3 shows the
ROM byte data.
Figure 2–3 Option ROM Byte Data
LJ-00101-TI0
Byte 0
Byte 1
Byte 2
Byte 3
Byte 4
Byte 5
Byte 6
Byte 7
Byte 8
Last Byte
Data Path Indicator
Reserved
Version
ROM Index Number
Manufacturing Check Data (55h)
Manufacturing Check Data (AAh)
Manufacturing Check Data (33h)
ROM Part Length
Reserved for ROM set Data
Checksum
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