@mrgs,
Programming and activating the DMA engine should be done using a descriptor. You should not program the DMA registers directly (except for DMACONFIG).
According to Table 32, next-ptr, stride (inner/outer, src/dst) and count (inner/outer) are all 16-bit values. The source and destination addresses are 32-bit each and can point to anywhere in the memory space.
Thus, in the sample descriptor, the configuration is to transfer bytes as a master w/o chaining DMA's. The strides for the inner loops are both 1 (meaning, a contiguous vector in memory), the inner loop count is 8 for transferring 8 bytes and the outer loop has only one iteration (so we transfer a 1-D contiguous array of bytes). The outer stride is not important here since there is no outer loop. Two values of 0 are just arbitrary. The addresses show copy from internal to external memory.
Once the DMACONFIG register is written with this descriptor's address and with a kick-start signal, the transfer begins.
Note that the descriptor's memory
must not be altered while the transfer is in progress, or some undefined behaviour will occur
BTW, the # prefix for immediates is not mandatory and is a matter of style.
by tono » Mon Dec 17, 2012 10:00 pm 
