OK, I can see many things about sectors of 512 bytes, this doesn't fit my
need at all, as I need 1024 bytes / sectors. I'd say sd_card library
shouldn't have anything related to sectors or the like, as it is something
related to file systems, and you may just use your SD-Card without
considering any of these.

But since I'm no SD expert, there could be a reason to do so. Still, setting
address with sd_start_read(sector) ends with accessing SD-card on a
byte-level, not sector.

Cheers,
Seb

2011/4/20 Sebastien Lelong <[email protected]>

> Hi Matt,
>
> Some more feedback about current sd_card.jal library:
>
>   - send_command() should be prefixed with sd_send_command() to avoid
> potential collision
>   - I wanted to use sd_data_byte, to read card byte by byte, but it seems
> already "infected" by some filesystems stuff: it increment a counter related
> to sector, dealing with 512 bytes.
>   - in the same procedure, there seems to be special values when reading
> SPI (eg. 0xFE). What if I need to read these values ? I don't understand the
> following loop:
>
>    if sd_byte_count == 0 then               -- beginning of sector read
>       while spi_master != 0xFE loop      -- wait till data is ready to read
>       end loop
>    end if
>
> Basically this is why my sample doesn't work, commenting the "while" loop
> fixes the issue.
>
> Shouldn't I use this procedure ? Shouldn't it be completely independent
> from filesystem concerns ?
>
> Thanks for your light !
>
> Cheers,
> Seb
>
>
>
> 2011/4/19 mattschinkel <[email protected]>
>
>> Sure, and also check if pragma inline is a good idea.
>>
>> Matt.
>>
>> On Apr 19, 12:33 pm, Sebastien Lelong <[email protected]>
>> wrote:
>> > 2011/4/19 mattschinkel <[email protected]>
>> >
>> > > I prefer to take the spi init procedure and split it into two.
>> >
>> > OK, do you want me to take care of this ?
>> >
>> > Cheers,
>> > Seb
>> >
>> >
>> >
>> > > spi_master_hw_set_mode(byte in mode)
>> > > spi_master_hw_set_speed(byte in speed)
>> >
>> > > The set speed procedure may not be used as often, however there are
>> > > some devices that require SPI commands to be slower then SPI data
>> > > transfers. For example, mp3 decoder vs1053b
>> >
>> > > Then add another alias to the sample
>> >
>> > > alias spi_master_set_mode is spi_master_hw_set_mode
>> >
>> > > Matt.
>> >
>> > > On Apr 19, 6:42 am, Sebastien Lelong <[email protected]>
>> > > wrote:
>> > > > OK, thanks for pointing this. How can we solve this in order
>> sd_card.jal
>> > > to
>> > > > be fully generic ? I remember we have the exact same problem with
>> > > ethernet
>> > > > libs.
>> >
>> > > > Cheers,
>> > > > Seb
>> >
>> > > > 2011/4/19 mattschinkel <[email protected]>
>> >
>> > > > > Thanks.
>> >
>> > > > > You may also want to pay attention to these lines (if you are
>> using
>> > > > > more then one SPI device that use different modes)
>> >
>> > > > >   -- put spi into mode 11
>> > > > >   if SD_ALWAYS_SET_SPI_MODE == TRUE then
>> > > > >      SSPCON_CKP = 1
>> > > > >      SSPSTAT_CKE = 0
>> > > > >   end if
>> >
>> > > > > All of my SPI libs use these lines so the devices can be used
>> > > > > together.
>> >
>> > > > > SD_ALWAYS_SET_SPI_MODE is defined in the sample.
>> >
>> > > > > Matt.
>> >
>> > > > > --
>> > > > > You received this message because you are subscribed to the Google
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>> > > > > To post to this group, send email to [email protected].
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>> > > > > [email protected].
>> > > > > For more options, visit this group at
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>> >
>> > > > --
>> > > > Sébastien Lelonghttp://www.sirloon.nethttp://sirbot.org
>> >
>> >
>>
>> --
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>>
>
>
> --
> Sébastien Lelong
> http://www.sirloon.net
> http://sirbot.org
>



-- 
Sébastien Lelong
http://www.sirloon.net
http://sirbot.org

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