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ROM Partitioning
C.1 Firmware EPROM Layout
By convention, all VAX 4000 systems implement a longword at physical
location 20040004 in the firmware FEPROM for the SIE. The layout of the SIE
is shown in Figure C–3. A description of each field is provided in Table C–2.
Figure C–3 SIE : System Identification Extension (20040004)
3 1
0 0
0 7
0 8
1 5
1 6
2 3
2 4
MLO-007700
SYS_TYPE
Version
SYS_SUB_TYPE
Variant
Table C–2 System Identification Extension
Field
Name
RW
Description
31:24
SYS_TYPE
ro
This field identifies the type of system for a specific
processor.
01 : Q22–bus single processor system.
23:16
VERSION
ro
This field indentifies the resident version of the
firmware encoded as two hexadecimal digits. For
example, if the banner displays V5.0, then this field
is 50 (hex).
15:8
SYS_SUB_
TYPE
ro
This field indentifies the particular system subtype.
01 : KA650
02 : KA640
03 : KA655
04 : KA670
05 : KA660
06 : KA680
07 : KA690
0C : KA675
0E : KA681
0F : KA691
10 : KA692
10 : KA694
7:0
VARIANT
ro
This field indentifies the particular system variant.
C–4 ROM Partitioning