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SD Card question?

Hello to anyone!

I'm designing SD host controller core and I have some question to someone who known about it. I've made SD controller with 1 bit data line and I want to make 4 bit data line interface with SD, but all the same after sending to SD Card ACMD6, data received by 1 wire.

I'm doing next:

(wait for 90 clock) -> CMD0 -> CMD55 -> ACMD41 (with repeate) -> CMD2

-> CMD3 -> -> CMD7 (with RCA) -> ACMD6 (4 bit) -> CMD17

One date line mode does work but 4 data line doesn't work.

Any ideas?

Thanks!

Reply to
Camelot
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What doesn't work?

Do you get any data at all?

One problem I had was with CRCs for 4 bit mode.

CRC's are computed on individual data lines, I made the mistake of using the final 8 bytes of data as the CRC's, but the bits are more like individual serial lines with individual 16 bit CRCS at the end of the data.

Rufus

Reply to
Rufus V. Smith

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