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DMA & SSP big endian

Hi,
I'm using LPC2478.
My board connected to Analog Device ADE7878 chip that has Fast SPI that send continusly data.
Its 3 wire protocol that start the CS bit then clock out 7*32 bits (total 7*4 bytes=28 bytes) then raise the CS - wait 30Micro Second and start again.
The Clock is about 4mhz.
I want to fill a large area (in sdram) with the data.
I use the DMA with SSP and it works perfect.
I connect the CS line also to EINT0 so I know when the transfer is finished and then I reprogram the destinatin address for the DMA to fill the next block.
My problem is that the data is 32 bit - big endian (most first) and I need to swap the bytes to use them as a 32 bit integer.
Because I deal with a lot of data I don't want to waste time of this swap.
I read that the DMA has a bit for Big Endian mode. But when I set it on I don't get data at all (all 0).

I belive I have misunderstood of the SBSIZE DBSIZE SWidth & DWidth in the DMACC1Control register.

Any help?

Regards,
Doron

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