Sun Microsystems StorEdge T3+, Service Manual

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Chapter 4 Controller Card Assembly 4-11
The following explains each field in the header.
TABLE 4-4
Channel Active LED Descriptions
Header Description
code_size
This is the size of the code without the header information.
This value must be a multiple of four. The real file size
should be
code_size
plus
sizeof
(EP_HEADER).
code_cksum The 32-bit checksum value of the code.
code_cksum
= sum
of all 32-bit words in code OR 0xF1.
code_start The execution starting location. For example, after
downloading level 3 code into RAM, the level 2 code jumps
to this location.
code_base The starting location for download. For example, the level 2
code downloads the level 3 code from ROM into RAM
starting at this location. However, notice that when the
starting location is 0x20000, the image in the file is loaded to
0x20040 in RAM. The first 0x40 bytes are occupied by the
header information. That is to say that the
code_base
includes the space occupied by the header information.
code_signature Each level of boot code has a unique signature. For example,
the level 3 signature is “P2L3”.
code_rev The revision of the code.
code_subrev
The subrevision of the code.
code_date The date stamp of the code. For example, 20001225 means
2000/12/25.
code_time The time stamp of the code. For example, 01020300 means
01:02:03.