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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