SDReadWriteRegistersDirect (Windows CE 5.0)
This function reads from or writes to the registers of an SDIO card.
SD_API_STATUS SDReadWriteRegistersDirect(SD_DEVICE_HANDLEhDevice,
SD_IO_TRANSFER_TYPEReadWrite,
UCHARFunction,
DWORDAddress,
BOOLEANReadAfterWrite,
PUCHARpBuffer,
ULONGBufferLength);
Parameters
- hDevice
[in] Handle to an SD bus device. - ReadWrite
[in] Value that indicates whether to read from or write to the registers of an SDIO card. A value of SD_IO_READ indicates a read operation. A value of SD_IO_WRITE indicates a write operation. - Function
[in] Function number. - Address
[in] Starting register address for the read or write operation. - ReadAfterWrite
[in] Value that indicates whether to perform a read operation following a write operation. If set to TRUE, a read is performed following a write operation. The read data is returned in pBuffer. - pBuffer
[in, out] Buffer to hold register data. - BufferLength
[in] Number of bytes to read or write.
Return Values
A return value of type SD_API_STATUS indicates success or failure.
Remarks
Direct I/O is intended for simple register access and requires a significant amount of overhead for each byte transferred. The preferred method for transferring large amounts of data is through the extended I/O command.
Requirements
OS Versions: Windows CE 5.0 and later.
Header: Sdcardddk.h.
Link Library: Sdcardlib.lib.
See Also
Secure Digital Card Driver Functions
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