I'm wondering how these values are determined too. I'm "following along at home" without any idea what I'm doing (though all the files, bytes, and offsets are matching with the tutorial... Also, if the original author finds this thread: amazing write-up - got me really interested in the topic!).
At the step where they remove the header with
dd if=uImage of=Image.lzma bs=1 skip=72
It results in a file that if I try and un compress it with `unlzma Image.lzma` it complains with "Compressed data is corrupt"
I don't know where the magic number "72" comes from. Is it likely that could be different on my machine (a mac)?
[edit: I think there's something else wrong - if I use `mkImage` to examine the uImage file I only get:
mkimage -l uImage
GP Header: Size 27051956 LoadAddr 78a267ff
The 72 bytes is from the difference between the uImage header and the lzma inside, from the post. 0x132b8-0x13270 = 72 (dec).
So you'll need to check what binimage says about your image, the uImage header isn't necessarily fixed in size. Also see the comment above about the --dd switch, though mind the reply to that pointing out you might want to check what it finds before just letting it write a pile of files.
At the step where they remove the header with
It results in a file that if I try and un compress it with `unlzma Image.lzma` it complains with "Compressed data is corrupt"I don't know where the magic number "72" comes from. Is it likely that could be different on my machine (a mac)?
[edit: I think there's something else wrong - if I use `mkImage` to examine the uImage file I only get:
Instead of image information]