When you say the download doesn't work, what do you mean?

When I try to download the "zImage" from  TFTP Server to my RAM 0x00200000 on
board,
the download process will stop . That is to say, it cannot download the whole
"zImage" file
but just a part of the "zImage " file. But it I download the "zImage" to my RAM
0x00100000 on
board, it will succeed to download and show a message "starting at
0x00100000..." and halt.

How much RAM do you have?

32M.
Notes that I want to download the "zImage" from remote TFTP Server via EHERNET
instead of  from local flash .
I have downloaded the FADSROM and 8xxROM packages and researched them.
They all seem to download the "zImage" from local flash disk, not from remote
TFTP server via ETHERNET. I think the latter is easy to debug applications,
right?
Do you think it will make any difference between these two cases?
When I download the "zImage" from remote TFTP server  via ethernet to RAM
0x00200000 board , how can I dispose the "zImage" at other address , and when
jumping there it will boot the kernel?
Any ideas?

Downloading zImage to 2MB should work.  You might
try downloading to 3 or 4MB.  You need to download the relocatable kernel
image (zImage) so that entirely fits in RAM, low enough that the top end of
zImage and any attached initrd doesn't over flow the top of RAM.  The
bootloader will copy the kernel low using 0x0 and up for its data structures
and executable.  The zImage must not conflict with the kernel executable or
data structures.  Putting the zImage at 0x00100000 is too low.  During the
boot load process, the kernel builds data structures upward in memory
depending on the size of the kernel and number of options.

Copying the image to flash depends on the hardware and flash ROM chips.  You
will have to write
a flash ROM erase and writing program.  Assuming your board has flash, find
the data sheet and read up on the write programming algorithm.  The zImage
and initrd can load into ROM and the boot
loader can execute fromm flash rom.

Sorry, I still don't understand your meaning.
When you say "copy image to flash", what does the image contain?
bootrom codes+kernel+RootFileSystems or kernel+RootFileSystems? If so, in what
file format can I write it into flash?
Best regards,
dony

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