Specifications

17 January 1997 – Subject to Change
SROM Initialization C–5
Special ROM Header
C.6 Special ROM Header
The MAKEROM tool is used to place a special header on ROM image files. The
SROM allows the system (flash) ROM to contain several different ROM images,
each with its own header. The header informs the SROM where to load the image,
and whether or not it has been compressed with the MAKEROM tool. The header is
optional for system ROMs containing a single image. If the header does not exist, the
complete 1MB system flash ROM is loaded and executed starting at physical address
zero. For more information on the MAKEROM tool, refer to the Alpha
Microprocessors Evaluation Board Software Design Tools User’s Guide.
Figure C–1 shows the header content.
Figure C–1 Special Header Content
Validation Pattern 5A5AC3C3
0x00
31 0
MK-2306-19
Hdr Rev<7:0>
FW ID<15:8>
Inverse Validation Pattern A5A53C3C
Header Size (Bytes)
Image Checksum
Image Size (Memory Footprint)
Decompression Flag
Destination Address Lower Longword
Destination Address Upper Longword
Rsvd<31:24>
Flash ROM Image Size
Optional Firmware ID<31:0>
Optional Firmware ID<63:32>
Header Checksum (excluding this field)
0x04
0x08
0x0C
0x10
0x14
0x18
0x1C
0x24
0x2C
0x30
0x20
0x28
Offset
ROM Offset <31:2>
ROM Offset Valid <0>
Hdr Rev Ext<23:16>
0x34