Another thing that is a bit of a pain, is that the chip select line
must stay active during your entire read. You can't read a few bytes
then store them onto a separate SPI memory like 23k256 and then
continue reading from where you left off.

Maybe a look in the specification will tell you if it is ok to stop
reading by de-activating the chip select line. I don't really know for
sure. I suppose the stop read procedure does make the chip select line
go inactive.

I guess I never really had a need for partial reads :)

Matt.

On Apr 21, 4:13 am, Sebastien Lelong <[email protected]>
wrote:
> 2011/4/21 mattschinkel <[email protected]>
>
> > Great, so I may just add that optional constant SD_BLOCK_SIZE
>
> OK
>
> > You should also be careful about stopping your reads in the middle of
> > a block. I think the working (but not proper) way to stop in the
> > middle of a block is to de-activate the chip select line. If the chip
> > select line stays active, the sd card will assume the next thing you
> > try to do is a read. Even if you are trying to send a command.
>
> > The proper way of course is to just dummy read the rest of the block.
>
> OK. I'm currently using sd_stop_read(), so I guess this isn't the proper way
> as it doesn't read remaining block's bytes.
>
> > I do wish to improve the lib and I very much appreciate your input!
>
> I'll give feedback as much as I can, but I'm not completely understanding
> SD-cards and just stick to available API :)
>
> Cheers,
> Seb
>
>
>
>

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