User`s manual

4.4 Flash ROM (System ROM)
Figure 4–5 Special Header Content
LJ04171A.AI5
Validation Pattern 5A5AC3C3
Inverse Validation Pattern A5A53C3C
Header Rev<7:0>Reserved<31:16>
Image Checksum
Image Size (Memory Footprint)
Decompression Flag
Destination Address Lower Longword
Destination Address Upper Longword
Header Size (Bytes)
Optional Firmware ID<63:32>
Header Checksum (excluding this field)
00
0C
10
14
08
1C
20
24
18
2C
30
28
04
Firmware ID<15:8>
Optional Firmware ID<31:0>
Flash ROM Image Size
31 00
Table 4–2 describes each entry in the special header.
Table 4–2 Special Header Entry Descriptions
Entry Description
Validation and inverse
validation pattern
This quadword contains a special signature pattern used to
validate that the special ROM header has been located. The
pattern is 5A5AC3C3A5A53C3C.
Header size (bytes) This longword contains the size of the header block, which
varies among versions of the header specification.
When the header is located, SROM code determines where
the image begins based on the header size. Additional data
added to the header will be ignored by older SROM code.
A header size of 32 bytes implies version 0 of the header
specifications.
Image checksum This longword is used to verify the integrity of the ROM.
Image size
(memory footprint)
The image size is used by the SROM code to determine how
much of the flash ROM should be loaded.
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4–8 Functional Elements