Instruction manual

The components of the ROM header are:
Component Address Length Description
ROM Width Base + 0
16
1 Byte The width of the ROM in bytes. The
system ROM width is 1, while the I/O
ROM width is 4.
ROM Stride Base + 4
16
1 Byte The address stride of the ROM. This
must be a 4.
ROM Size Base + 8
16
1 Byte The size of the ROM in bytes divided by
8192.
Slot Size Base + C
16
1 Byte The minimum TURBOchannel slot size
required by the option module divided by
4 194 304 (4 MB).
Pattern fields Base + 10
16
16
Bytes
Four pattern fields used for test
purposes and also part of a signature
of a ROM header. The patterns are 55,
00, AA, and FF.
Firmware revision Base +20
16
8 Bytes A field of 8 ASCII characters of version
information. Only graphic ASCII codes
are allowed (0x20-0x7E). Unused
characters must contain the blank
character (20
16
).
Vendor name Base + 40
16
8 Bytes A field of 8 ASCII characters indicating
the module manufacturer. Only graphic
ASCII codes are allowed (0x20-0x7E).
Unused characters must contain the
blank character (20
16
). The vendor name
will be ‘‘DEC’’ on both the system and
I/O ROMs.
Module name Base + 60
16
8 Bytes A field of 8 ASCII characters indicating
the module name. Only graphic ASCII
codes are allowed (0x20-0x7E). Unused
characters must contain the blank
character (20
16
). For the 500/800/900
models, the module name of the system
ROM is ‘‘FLAM_SYS’’ and the module
name of the I/O ROM is ‘‘FLAM_IO.’’ For
400/600/700 models the module name
of the system ROM is ‘‘SAND_SYS’’ and
the module name of the I/O ROM is
‘‘SAND_IO.’’ In 300 models, the module
name of the system ROM is ‘‘PELI_SYS’’
and the name of the I/O ROM is ‘‘PELI_
IO.’’
Firmware type Base + 80
16
4 Bytes A field of 4 ASCII characters indicating
the type of firmware present in the
module ROM. Only graphics ASCII
characters are allowed (0x20-0x7E).
Unused characters must contain the
blank character (20
16
). The firmware
type will be "ALPH" to denote Alpha
AXP code.
13–4 DEC 3000 AXP Firmware ROMs