1.34.6.7 HSMCI_DmaSetup Function
C
void HSMCI_DmaSetup ( uint8_t* buffer, uint32_t numBytes, HSMCI_DATA_TRANSFER_DIR direction )
Summary
Sets up the DMA for data tranfers.
Description
The client of the HSMCI PLIB must set up the DMA before initiating a data transfer.
Precondition
HSMCI_Initialize() must have been called first.
Parameters
Param | Description |
---|---|
buffer | Pointer to the read or write buffer depending on the direction specified |
numBytes | Number of bytes to read or write |
direction | Enumeration of HSMCI_DATA_TRANSFER_DIR type identifying the tranfer direction |
Returns
None.
Example
uint8_t readBuffer[512]; HSMCI_DataTransferFlags transferFlags; transferFlags.isDataPresent = true; transferFlags.transferDir = HSMCI_DATA_TRANSFER_DIR_READ; transferFlags.transferType = HSMCI_DATA_TRANSFER_TYPE_SINGLE; // Set up the DMA to read 512 btyes of data HSMCI_DmaSetup(readBuffer, 512, HSMCI_DATA_TRANSFER_DIR_READ); // Send command to read one block of data from SD card starting at block address 100 HSMCI_CommandSend(17, 100, HSMCI_CMD_RESP_R1, transferFlags);
Remarks
None.