最近在做sd卡驱动的移植,读手册时有几个参数看不明白。比如,我板子的sd卡控制器寄存器有两个位可以设置sd卡dma的类型,原文如下:
DMA type:
It indicates which DMA transaction type is used. These 2 bits are
valid when the DMA_EN is enabled.
00: Single read/write
01: Burst 4 read/write
10: Burst 8 read/write
11: Revised
请问这4个dma类型分别是什么意思?尤其是01和10这两个,谢谢。 |