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Nations Technologies Inc.
Tel
:
+86-755-86309900
:
Address: Nations Tower, #109 Baoshen Road, Hi-tech Park North.
Nanshan District, Shenzhen, 518057, P.R.China
Figure 18-5 SDIO continuous write operation
SDIO function description
Figure 18-6 is a block diagram of SDIO structure:
SDIO adapter: It consists of control unit, command unit and data unit. The control unit generates a clock signal,
and the command unit and data unit manage the transmission of commands and data respectively, thereby
realizing the related functions of the MMC/SD/SD I/O card. .
AHB bus interface: used to operate the FIFO unit of the register control data transmission in the SDIO adapter
module, and generate interrupt and DMA request signals.
Figure 18-6 SDIO block diagram
18.3.1
SDIO adapter
The following figure is a simplified block diagram of the SDIO adapter:
command
command
response
数据停止操作
SDIO_CMD
SDIO_DATA
host to devise
host to devise
device to host
response
The data flow
device to host
The stop command stops data transfer
host to devise
Data stop operation
Data write operation
SDIO
AHB bus
interface
SDIO
adapter
SDIOCLK
HCLK/2
Interrupt and
DMA requests
AHB bus
SDIO_CLK
SDIO_CMD
SDIO_DAT[7:0]
Control unit
Command
channel
Data channel
Register
FIFO