ST STM32F412 User Manual

RM0402 Rev 6 869/1163
RM0402 Secure digital input/output interface (SDIO)
921
Command path
The command path unit sends commands to and receives responses from the cards.
Figure 313. 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 314 on
page 870). When the response is received, the received CRC code and the
internally generated code are compared, and the appropriate status flags are set.
MSv36078V1
Adapter registers
CMD
Status
flag
CRC
Shift
register
CMD
To control unit
SDIO_CMDin
SDIO_CMDout
To APB2 interface
Control
logic
Command
timer
Argument
Response
registers

ST STM32F412 Specifications

General

Brand	ST
Model	STM32F412
Category	Microcontrollers
Language	English