EFM32 Gecko Software Documentation  efm32g-doc-5.1.2

Detailed Description

This module implements the SPI layer needed to control a micro SD card.

Macros

#define ACMD13   (13 | 0x80)
 
#define ACMD23   (23 | 0x80)
 
#define ACMD41   (41 | 0x80)
 
#define CMD0   (0)
 
#define CMD1   (1)
 
#define CMD10   (10)
 
#define CMD12   (12)
 
#define CMD16   (16)
 
#define CMD17   (17)
 
#define CMD18   (18)
 
#define CMD23   (23)
 
#define CMD24   (24)
 
#define CMD25   (25)
 
#define CMD41   (41)
 
#define CMD55   (55)
 
#define CMD58   (58)
 
#define CMD8   (8)
 
#define CMD9   (9)
 

Functions

int MICROSD_BlockRx (uint8_t *buff, uint32_t btr)
 Receive a data block from micro SD card. More...
 
int MICROSD_BlockTx (const uint8_t *buff, uint8_t token)
 Send a data block to micro SD card. More...
 
void MICROSD_Deinit (void)
 Deinitialize SPI peripheral. Turn off the SPI peripheral and disable SPI GPIO pins.
 
void MICROSD_Deselect (void)
 Deselect the micro SD card and release the SPI bus.
 
void MICROSD_Init (void)
 Initialize the SPI peripheral for microSD card usage. SPI pins and speed etc. is defined in microsdconfig.h.
 
void MICROSD_PowerOff (void)
 Turn off micro SD card power. DK doesn't support socket power control, only disable the SPI clock.
 
void MICROSD_PowerOn (void)
 Turn on micro SD card power. DK doesn't support socket power control, only enable the SPI clock.
 
int MICROSD_Select (void)
 Select the micro SD card and wait for the card to become ready. More...
 
uint8_t MICROSD_SendCmd (uint8_t cmd, DWORD arg)
 Send a command packet to micro SD card. More...
 
void MICROSD_SpiClkFast (void)
 Set SPI clock to maximum frequency.
 
void MICROSD_SpiClkSlow (void)
 Set SPI clock to a low frequency suitable for initial card initialization.
 
bool MICROSD_TimeOutElapsed (void)
 Check if timeout value set with MICROSD_TimeOutSet() has elapsed. More...
 
void MICROSD_TimeOutSet (uint32_t msec)
 Set a timeout value. The timeout value will be decremented towards zero when SPI traffic to/from the micro SD card takes place. Use MICROSD_TimeOutElapsed() to check if timeout has elapsed. More...
 
uint8_t MICROSD_XferSpi (uint8_t data)
 Do one SPI transfer. More...
 

Macro Definition Documentation

#define ACMD13   (13 | 0x80)

SD_STATUS (SDC)

Definition at line 48 of file microsd.h.

#define ACMD23   (23 | 0x80)

SET_WR_BLK_ERASE_COUNT (SDC)

Definition at line 53 of file microsd.h.

#define ACMD41   (41 | 0x80)

SEND_OP_COND (SDC)

Definition at line 43 of file microsd.h.

#define CMD0   (0)

GO_IDLE_STATE

Definition at line 41 of file microsd.h.

Referenced by MICROSD_SendCmd().

#define CMD1   (1)

SEND_OP_COND

Definition at line 42 of file microsd.h.

#define CMD10   (10)

SEND_CID

Definition at line 46 of file microsd.h.

#define CMD12   (12)

STOP_TRANSMISSION

Definition at line 47 of file microsd.h.

Referenced by MICROSD_SendCmd().

#define CMD16   (16)

SET_BLOCKLEN

Definition at line 49 of file microsd.h.

#define CMD17   (17)

READ_SINGLE_BLOCK

Definition at line 50 of file microsd.h.

#define CMD18   (18)

READ_MULTIPLE_BLOCK

Definition at line 51 of file microsd.h.

#define CMD23   (23)

SET_BLOCK_COUNT

Definition at line 52 of file microsd.h.

#define CMD24   (24)

WRITE_BLOCK

Definition at line 54 of file microsd.h.

#define CMD25   (25)

WRITE_MULTIPLE_BLOCK

Definition at line 55 of file microsd.h.

#define CMD41   (41)

SEND_OP_COND (ACMD)

Definition at line 56 of file microsd.h.

#define CMD55   (55)

APP_CMD

Definition at line 57 of file microsd.h.

Referenced by MICROSD_SendCmd().

#define CMD58   (58)

READ_OCR

Definition at line 58 of file microsd.h.

#define CMD8   (8)

SEND_IF_COND

Definition at line 44 of file microsd.h.

Referenced by MICROSD_SendCmd().

#define CMD9   (9)

SEND_CSD

Definition at line 45 of file microsd.h.

Function Documentation

int MICROSD_BlockRx ( uint8_t *  buff,
uint32_t  btr 
)

Receive a data block from micro SD card.

Parameters
[out]buffData buffer to store received data.
btrByte count (must be multiple of 4).
Returns
1:OK, 0:Failed.

Definition at line 178 of file microsd.c.

References _USART_FRAME_DATABITS_MASK, MICROSD_XferSpi(), USART_CMD_CLEARRX, USART_CMD_CLEARTX, USART_CTRL_BYTESWAP, USART_FRAME_DATABITS_SIXTEEN, and USART_STATUS_RXDATAV.

int MICROSD_BlockTx ( const uint8_t *  buff,
uint8_t  token 
)

Send a data block to micro SD card.

Parameters
[in]buff512 bytes data block to be transmitted.
tokenData token.
Returns
1:OK, 0:Failed.

Definition at line 253 of file microsd.c.

References _USART_FRAME_DATABITS_MASK, MICROSD_XferSpi(), USART_CMD_CLEARRX, USART_CMD_CLEARTX, USART_CTRL_BYTESWAP, USART_FRAME_DATABITS_SIXTEEN, USART_STATUS_TXBL, and USART_STATUS_TXC.

int MICROSD_Select ( void  )

Select the micro SD card and wait for the card to become ready.

Returns
1:Successful, 0:Timeout.

Definition at line 135 of file microsd.c.

References GPIO, and MICROSD_Deselect().

Referenced by MICROSD_PowerOff(), and MICROSD_SendCmd().

uint8_t MICROSD_SendCmd ( uint8_t  cmd,
DWORD  arg 
)

Send a command packet to micro SD card.

Parameters
[in]cmdCommand byte.
[in]argArgument.
Returns
Response value.

Definition at line 342 of file microsd.c.

References CMD0, CMD12, CMD55, CMD8, MICROSD_Deselect(), MICROSD_Select(), MICROSD_SendCmd(), and MICROSD_XferSpi().

Referenced by MICROSD_SendCmd().

bool MICROSD_TimeOutElapsed ( void  )

Check if timeout value set with MICROSD_TimeOutSet() has elapsed.

Returns
True if timeout has elapsed.

Definition at line 433 of file microsd.c.

void MICROSD_TimeOutSet ( uint32_t  msec)

Set a timeout value. The timeout value will be decremented towards zero when SPI traffic to/from the micro SD card takes place. Use MICROSD_TimeOutElapsed() to check if timeout has elapsed.

Parameters
[in]msecMillisecond timeout value (very approximate).

Definition at line 422 of file microsd.c.

uint8_t MICROSD_XferSpi ( uint8_t  data)

Do one SPI transfer.

Parameters
dataByte to transmit.
Returns
Byte received.

Definition at line 112 of file microsd.c.

References USART_SpiTransfer().

Referenced by MICROSD_BlockRx(), MICROSD_BlockTx(), MICROSD_Deselect(), and MICROSD_SendCmd().