Hi,
I followed the procedure of multi-block write operation using EDMA. spruh77.pdf (page 1260). As it is mentioned,i set DMATRIG bit in MMCCMD register to trigger first data transfer. And i have configured EDMA 3_0 PaRam before set DMATRIG bit. When i triggered DMA, i found that the global region of ER(event register)in EDMA3_0 was altered from 0 to 0x00020000(Since in EDMA3CC0 MMCSD0_xmt sychronization event is 17).EDMA3_0 can work pretty well.
Now EDMA3_0 was used for Ping-pong buffering from AD to DDR,and i create a thread to processing the data that received from AD. In the mean time, saving original data from DDR to SD card(by writing to SD card block).I think if i use EDMA3_0 to sample the input and use EDMA3_1 to save data,some conflicts problems can be avoided. I configured EDMA3_1 PaRam the same as i use EDMA3_0 PaRam, but when i set DMATRIG bit, EDMA3_1 ER did not change.Since there is no synchronazation event coming, no data transmission.That is what i am confused now.
Here are the problems:
1.Setting DMATRIG bit in MMCSD register can lead to EDMA3_0 ER changed.But it has no effect on EDMA3_1 ER(also the global region)? why?
2.How can i use EDMA3_1 CC0 event 17(MMCSD0_XMT)to do my work?(EDMA3_0 CC0 has tested well performed)?Do i need to configure some registers to let EDMA3_1 work(i have checked PSC1 EDMA3_1,it is powered up)?
Best regards
