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!

"Camelot" <camelot@hightech-td.com> wrote in message 
news:10f20c13.0502251201.6ea63728@posting.google.com...
> 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!

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