That's a very valid question.

This actually isn't an error, it's a normal opertion of Lolo. This happens when Lolo doesn't see another .elf header at the end of the checksum of the elf file that it just loader. This isn't anything to worry about but I can understand how this might be confusing at first.

Regards,

yu_yx,

Aaron is exactly right. Basically, LoLo only loads the executable and data parts of an elf file. Any debug symbols etc. are ignored. That is the reason the LoLo outputs: "... running md5sum on the _loaded_ portion of the file: ..." What we are trying to make clear is we only load the parts of the file that _must_ be loaded.

To verify that your file was loaded correctly, do the following at a Cygwin prompt or on a Linux box:

1) arm-elf-objcopy -O binary your_program.elf foo.raw
2) md5sum foo.raw
3) rm foo.raw

The first step uses the binary utility objcopy to strip out all of the elf headers, debug portions, etc. of your program's elf file and create a new raw binary file named foo.raw. This is exactly what LoLo is doing to your program as it loads it into SDRAM.

The second step just calculates an MD5SUM on that raw binary file. The output can be compared to LoLo's output.

Of course the last step just gets rid of that temporary binary file as you probably don't want it hanging around.

Hope this helps,

--mikee

Hi Aaron and Mikee,

Thanks for the clarifications.

The next problem I have is that I cannot save a binary image into the CompactFlash I've mounted.
I've mounted a compactflash device.
Load an elf file.
Execute the Burn Command.
But an error that says "unable to burn without a loaded flash image" appears.

Have I missed a step or this is not the right way to save a binary file into compactflash?

Below are the captures from TeraTerm:

Regards,
Yu



losh> mount fatfs /dev/cf

losh> load elf
loading from stdin:
R.
elf file type : 0x0002
machine type: 0028 version: 1
prog start addr : 0xc00c03fc
num prog headers: 1
num sect headers: 18
offset : 0x00008000 disk length: 0x000086ec mem len: 0x00008da4
phyaddr: 0xc00c0000 vaddr : 0xc00c0000 dl addr: 0xc00c0000
ignoring rest of file... 60785 bytes. done
running md5sum on the _loaded_ portion of the file:
82671ea7febebc03ddc580ff54dbe484 - addr: c00c0000 len: 000086ec

losh> burn /dev/cf
unable to burn without a loaded flash image
command failed
usage:
burn [device]
burns the already-loaded image into flash device 'device'
example:

yu_yx,

The LogicLoader does not currently support programming Compact Flash devices. Therefore, you won't be able to accomplish your immeadiate goal. Around here we typically use SanDisk USB devices to program Compact Flash cards. They are both inexpensive and reliable. I'm currently using a SanDisk "ImageMate" which is SanDisk part number SDDR-31.

Due to the above fact, the only valid target for the "burn" command is the resident flash memory array. The image you were loading was built for RAM (evident by the output; "loading from stdin: R."). That is why LoLo reported the error as; "unable to burn without a loaded flash image."

Hope this clears things up.

--mikee

Hi Mike,
thanks for your reply.
Is there anyway to auto run an elf file from a flash or CompactFalsh memory instead of the SRAM?
I'm asking this question because if I were to use this board in an embedded system, I cannot affort to link it to a PC to load the elf into the SRAM memory and load it on every power up.

Regards,
Yu YX

yu_yx,

You can certainly execute in place from Flash memory. However, you cannot execute in place from Compact Flash memory. LoLo provides a scripting capability to automatically launch an executable at board reset. You should check the LogicLoader's user manual for more information. There is a whole section in there describing bootime scripts.

--mikee