2011/4/21 mattschinkel <[email protected]>

> > But you can actually read byte-by-byte, using sd_data_byte pseudo-var ?
> You
> > don't necessarily have to deal with a 512-bytes buffer.
>
> Yes, you can maybe read byte-by-byte, but you can't write byte-by-
> byte. You have to write the entire block.
>

OK


>
> > ... this means sd_card is "infected" (no offense :)) with FAT32 concerns.
> > Not a big deal in this case (start at 0, assume next is at 512), because
> > filesystems blocks are mutiple of 512. But if there's something more
> > FAT32-specific, it should be removed to be as generic as possible, so
> other
> > can build on top of it without finding weird workaround. AFAIK there's
> > currently no such case !
>
> If you want, we can add some user constants and improve the lib.
>

As far I can see, and now that I better understand, I don't see such need
anymore...


>
> Maybe this:
> address = address * 512
>
> can be changed to this:
> address = address * SD_BLOCK_SIZE
>

... though using SD_BLOCK_SIZE instead of hard-coded 512 is always a good
idea :)
This leaves room for easy experiments about this parameter.


> Is there a need for block size to be variable? Is there a need for
> blocks to not start at byte 0?
>

No, I'd say there's no need not to start at 0, if you're using a "standard"
filesystem (I mean FS using mutliple of 512)


>
> Adding this feature may be desirable (with warning about HC cards). Do
> you also wish that fat32 could use smaller blocks?
>

No, and I'm not sure what would be the benefit ?


Cheers,
Seb

-- 
You received this message because you are subscribed to the Google Groups 
"jallib" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to 
[email protected].
For more options, visit this group at 
http://groups.google.com/group/jallib?hl=en.

Reply via email to