RM0008
Secure digital input/output interface (SDIO)
Depending on the TXACT and RXACT flags, the FIFO can be disabled, transmit enabled, or
receive enabled. TXACT and RXACT are driven by the data path subunit and are mutually
exclusive:
The transmit FIFO refers to the transmit logic and data buffer when TXACT is
asserted
The receive FIFO refers to the receive logic and data buffer when RXACT is
asserted
Transmit FIFO:
Data can be written to the transmit FIFO through the AHB interface when the SDIO is
enabled for transmission.
The transmit FIFO is accessible via 32 sequential addresses. The transmit FIFO
contains a data output register that holds the data word pointed to by the read pointer.
When the data path subunit has loaded its shift register, it increments the read pointer
and drives new data out.
If the transmit FIFO is disabled, all status flags are deasserted. The data path subunit
asserts TXACT when it transmits data.
Table 126. Transmit FIFO status flags
Flag
TXFIFOF
TXFIFOE
TXFIFOHE
TXDAVL
TXUNDERR
Description
Set to high when all 32 transmit FIFO words contain valid data.
Set to high when the transmit FIFO does not contain valid data.
Set to high when 8 or more transmit FIFO words are empty. This flag can be used
as a DMA request.
Set to high when the transmit FIFO contains valid data. This flag is the inverse of
the TXFIFOE flag.
Set to high when an underrun error occurs. This flag is cleared by writing to the
SDIO Clear register.
Receive FIFO
When the data path subunit receives a word of data, it drives the data on the write
databus. The write pointer is incremented after the write operation completes. On the
read side, the contents of the FIFO word pointed to by the current value of the read
pointer is driven onto the read databus. If the receive FIFO is disabled, all status flags
are deasserted, and the read and write pointers are reset. The data path subunit
asserts RXACT when it receives data. Table 127 lists the receive FIFO status flags.
The receive FIFO is accessible via 32 sequential addresses.
Doc ID 13902 Rev 9
469/995
相关PDF资料
MCBTMPM330 BOARD EVAL TOSHIBA TMPM330 SER
MCIMX25WPDKJ KIT DEVELOPMENT WINCE IMX25
MCIMX53-START-R KIT DEVELOPMENT I.MX53
MCM69C432TQ20 IC CAM 1MB 50MHZ 100LQFP
MCP1401T-E/OT IC MOSFET DRVR INV 500MA SOT23-5
MCP1403T-E/MF IC MOSFET DRIVER 4.5A DUAL 8DFN
MCP1406-E/SN IC MOSFET DVR 6A 8SOIC
MCP14628T-E/MF IC MOSFET DVR 2A SYNC BUCK 8-DFN
相关代理商/技术参数
MCBSTM32EXLU 功能描述:开发板和工具包 - ARM EVAL BOARD + ULINK2 FOR STM32F103ZG RoHS:否 制造商:Arduino 产品:Development Boards 工具用于评估:ATSAM3X8EA-AU 核心:ARM Cortex M3 接口类型:DAC, ICSP, JTAG, UART, USB 工作电源电压:3.3 V
MCBSTM32EXLU-ED 制造商:ARM Ltd 功能描述:KEIL STM STM32EXL EVAL BOARD
MCBSTM32EXLUME 功能描述:开发板和工具包 - ARM EVAL BOARD + ULINKME FOR STM32F103ZG RoHS:否 制造商:Arduino 产品:Development Boards 工具用于评估:ATSAM3X8EA-AU 核心:ARM Cortex M3 接口类型:DAC, ICSP, JTAG, UART, USB 工作电源电压:3.3 V
MCBSTM32F200 功能描述:开发板和工具包 - ARM EVAL BOARD FOR STM STM32F207IG RoHS:否 制造商:Arduino 产品:Development Boards 工具用于评估:ATSAM3X8EA-AU 核心:ARM Cortex M3 接口类型:DAC, ICSP, JTAG, UART, USB 工作电源电压:3.3 V
MCBSTM32F200U 功能描述:开发板和工具包 - ARM EVAL BOARD FOR STM STM32F207IG + ULINK2 RoHS:否 制造商:Arduino 产品:Development Boards 工具用于评估:ATSAM3X8EA-AU 核心:ARM Cortex M3 接口类型:DAC, ICSP, JTAG, UART, USB 工作电源电压:3.3 V
MCBSTM32F200UME 功能描述:开发板和工具包 - ARM EVAL BOARD FOR STM STM32F207IG ULINK-ME RoHS:否 制造商:Arduino 产品:Development Boards 工具用于评估:ATSAM3X8EA-AU 核心:ARM Cortex M3 接口类型:DAC, ICSP, JTAG, UART, USB 工作电源电压:3.3 V
MCBSTM32F200UME-ED 制造商:ARM Ltd 功能描述:KEIL STM32F207IG EVAL BOARD
MCBSTM32F400 功能描述:开发板和工具包 - ARM EVAL BOARD FOR STM STM32F407IG RoHS:否 制造商:Arduino 产品:Development Boards 工具用于评估:ATSAM3X8EA-AU 核心:ARM Cortex M3 接口类型:DAC, ICSP, JTAG, UART, USB 工作电源电压:3.3 V