F28M35x dma_ram_to_ram routine

I have a problem about the routine of "dma_ram_to_ram". I put the DMABuf1 and DMABuf2 into the "Wactch Expressions",and I have some queries.According to the routine,the range  to value of DMABuf1 is from 0 to 1023 ,the DMABuf1 is 0xFFFF.After it runs,I notice that the range  to value of DMABuf1 is from 0 to 65535 in "Watch expressions",the DMABuf2 does.So  I am a little overwhelmed,now. Thank you!