RM0090 Secure digital input/output interface (SDIO)
Doc ID 018909 Rev 4 852/1422
Command path
The command path unit sends commands to and receives responses from the cards.
Figure 316. SDIO adapter command path
● Command path state machine (CPSM)
– When the command register is written to and the enable bit is set, command
transfer starts. When the command has been sent, the command path state
machine (CPSM) sets the status flags and enters the Idle state if a response is not
required. If a response is required, it waits for the response (see Figure 317 on
page 853). When the response is received, the received CRC code and the
internally generated code are compared, and the appropriate status flags are set.
ai15900
CMD
Status
flag
Control
logic
Command
timer
CRC
Argument
Shift
register
CMD
Response
registers
To control unit
SDIO_CMDin
SDIO_CMDout
To APB2 interface
Adapter registers
To Next Page
Loading...
Need help?
General
