SD Card question?

Do you have a question? Post it now! No Registration Necessary

Translate This Thread From English to

Threaded View
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!

Re: SD Card question?

Quoted text here. Click to load it

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



Site Timeline