edma on dspi is so ineffective

Discussion created by JIAN YAN on Nov 25, 2011
Latest reply on Nov 29, 2011 by JIAN YAN

 I am working on the powerfull mcf54415,In my eyes ,the edma can get all out of the chip,but when i dive into the spi code, i was comfused. the edma did nothing ,but make thing conplicate.it just transfer 16 byte a time, then in the enoq interrupt ,it trigger rx edma channel to get the rx byte to dma buffer, then copy to user buffer,SO what the use of edma.

  Can any one give a explain? Can i make the dma to transfer 1MB a time with just a interrupt?