Are there special considerations in making a bottable microSD for RP3's?

[Dale Amon]

I'm about to embark on a product development based on an RP3b+
and will need to be able to generate my own preinit'd SD's.

The first step is obviously mastering a simple copy. Thus far I
am coming up fail on all attempts.

I tried a dd of the Vilros 16GB card to file on my laptop. I have
then written it back to 32GB and 16GB keys; I have also downloaded
a raspian img and tried writing it to 32GB and 16GB keys.

None of them show a boot screen on my HDMI screen. However I can
swap back to the Vilros chip on this RP3b+ and the boot splash
comes up fine.

I have a feeling that a few pointers might show me the problem.
It might be the hardware I am using: I have tried the T500 laptops
direct SDCard slot using adaptors cards from two different vendors;
I have tried using an old Christallo multi-format card reader/writer.
Perhaps there is some issue with them. Or... perhaps there is something
wrong with the way I am dd'ing.

Although I have a lot of experience with bringing up bare machine,
it has been with larger machine and boot media. My experience with
the SD cards as other than something I use in my camera and phone
is nil. So basically, I am not a newbie in general but I am a
NOOB on SD card boot drives.

I look forward to some pointers to get over the initial learning
wall.

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| Dale Amon Immortal Data, Las Cruces Airport |
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