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ashpigel wrote:
> Hi All,
> I am  going to use PIC microcontroller as SD card (SPI mode) controller by
> the SPI interface of the PIC. Does anyone knows what is the effective baud
> rate of SD in SPI mode? I means what is the actually data transfer rate
> after removing the protocol added data, I am intending to work with the SPI
> in 25Mhz.

Depends on a few factors:
- -> Are you using DMA?
- -> Are you doing bulk transfers or block by block
- -> How cheap the memory card is! I've had the pleasure of
   working with one that spend ages doing unknown wizardry
   while the system waited for data to be ready.

Without the useless card I mentioned above I got 1.5 MByte / sec without
any particular optimisations with a PIC18F4620.


- --
Brendan Gillatt | GPG Key: 0xBF6A0D94
brendan {a} brendangillatt (dot) co (dot) uk
http://www.brendangillatt.co.uk
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Hi All,
I am  going to use PIC microcontroller as SD card (SPI mode) controller by
the SPI interface of the PIC. Does anyone knows what is the effective baud
rate of SD in SPI mode? I means what is the actually data transfer rate
after removing the protocol added data, I am intending to work with the SPI
in 25Mhz.

Thanks
   Aharon  

	   
					
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