Micro-SD card initialisation-problem

Hello all,

I've connected a Micro-SD card to my printerport (using very simple 5v to
3v voltage-step-down by three diodes and a resistor, signal step-down by a
1k8, 3k3 resistor combination), and am attempting to read from it.

The problem is that I can't seemto be able to get past the
initialisation-process. I can send a CMD0 to the card, and a CMD8 too
(multiple times), but whenever I try to enter a CMD1 or ACMD41 (CMD55
followed by a CMD41) loop I can write the commands once, sometimes 5 times
and than the card stops responding (does not return any status-byte in about
a two seconds). It does however respond to a re-start though (I can than
again write a CMD0 and get a response).

I've currently tried numerous things and read about 8 to 12 different
documents (apart from a number of PDFs) that have to do with communicating
with a MicroSD card, but have not found any indication to what the cause of
the above problem might be.

In short : if anyone knows what I should be doing to solve it I would be
gratefull.

Regards,
Rudy Wieser



.

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