參考一下
PIO Mode 0: The fastest data transfer rate reaches 3.3Mbyte/sec
PIO Mode 1: The fastest data transfer rate reaches 5.2Mbyte/sec
PIO Mode 2: The fastest data transfer rate reaches 8.3Mbyte/sec
PIO Mode 3: The fastest data transfer rate reaches 11.1Mbyte/sec
PIO Mode 4: The fastest data transfer rate reaches 16.6Mbyte/sec
DMA Mode 0: The fastest data transfer rate reaches 4.16Mbyte/sec
DMA Mode 1: The fastest data transfer rate reaches 13.3Mbyte/sec
DMA Mode 2: The fastest data transfer rate reaches 16.6Mbyte/sec
ULTRA DMA Mode 3: The fastest data transfer rate reaches 33Mbyte/sec
ULTRA DMA Mode 4: The fastest data transfer rate reaches 66Mbyte/sec
ULTRA DMA Mode 5: The fastest data transfer rate reaches 100Mbyte/sec
ULTRA DMA Mode 6: The fastest data transfer rate reaches 133Mbyte/sec
不太可能同一條排線一台可以用DMA,一台不能用才對
會不會是排線的問題