12.1實驗內容

通過本實驗主要學習以下內容：

• SDIO操作原理
• SD卡讀寫實現

12.2實驗原理

SD卡是一種主要以Nand Flash作為存儲介質，具有體積小、數據傳輸速度快以及支持熱插拔的優點。如今，已被廣泛應用于數碼相機、便攜式移動設備以及手機等多種設備中。SD卡的驅動一般有SPI接口或SDIO接口，本例程介紹使用GD32F4xx的SDIO接口驅動SD卡的實現。

12.2.1SD卡基礎知識

SD卡:secure digital memory card是一種安全存儲器件。屬性是快閃存儲器（flash eeprom），功能用來存儲數據。

SD卡雖然是薄薄的一片，但是它并不是一個整體，而是由大量的集成電路組成。SD卡的內部結構如下圖所示，主要由信號端子，接口控制器和存儲區組成。

SD卡主要有兩種模式，SD模式和SPI模式。不同模式下，接口定義不同。下面是SD卡的引腳。

兩種模式的接口定義如下

SD模式中，主要由VCC(電源)，VSS(GND)，CLK（時鐘，由主控提供)，CMD(命令)，DAT0-3(數據輸入輸出)，由6線制組成進行通信。SPI模式，主要采用4線制通信，除了電源地外，由MISO，MOSI，CLK，CS組成。下面簡單介紹SD模式的操作。

要驅動SD卡工作，主要涉及兩個步驟。第一個步驟是SD卡的識別過程。第二個步驟是對SD卡進行讀寫過程，即主機控制器和SD卡之間進行數據傳輸的過程。
要使SD卡能正常工作，一是要給SD卡供給穩定的電壓，二是要SD卡按用戶規定的方式工作。這兩項工作的實現，都是主機控制器通過給SD卡發送控制命令來實現的。
主機（SDIO控制器）要驅動SD卡工作，要使用許多的命令，包括應用層命令ACMD和 通用命令CMD.主機（SDIO控制器）把命令發送給SD卡，SD卡會作出回應，這里的回應叫做響應，響應命令分為6類，分別是R1、R1b、R2、R3、R6、R7。主機（SDIO控制器）給SD卡發送命令之后，SD卡會作出響應，響應中包含主機（SDIO控制器）需要的數據，這些數據有SD的信息，容量，和存儲數據等等。上面已經提到了，SD卡工作，主要是識別和數據傳輸，它的識別過程有些復雜，寫代碼的時候，可以參考協議給的初始化流程圖。數據傳輸包括讀和寫，單字節和多字節讀寫。下兩節描述識別初始化流程圖和數據讀寫時序圖。

1、讀寫數據的時序圖

SDIO與SD卡通信一般以數據塊的形式進行傳輸，SDIO(多)數據塊讀操作，如下圖所示。

SDIO(多)數據塊寫操作，如下圖所示。

2、命令格式
SDIO所有的命令和響應都是在SDIO_CMD引腳上面傳輸的，命令長度固定為48位，SDIO命令格式如下表所示。

3、寄存器
SDIO控制器的寄存器，主要設置SDIO控制器和命令的索引與參數。SD卡有5個寄存器CID,RCA,CSD,SCR.OCR。SD卡的信息從SD卡寄存器中獲取。

SD卡正常工作，就是根據SD卡初始化流程圖，發送命令，收到回復，直到流程結束。傳輸數據，也是根據讀寫時序圖，將要發送的數據放進命令中發送出去。

12.2.2SDIO模塊原理

SDIO為安全的數字輸入輸出接口，可以用于驅動SD卡、EMMC等，主要特征如下：

? e*MMC： 與多媒體卡系統規格書V4.2及之前的版本全兼容。有三種不同的數據總線模式：1位(默認)、4位和8位；
? SD卡： 與SD存儲卡規格版本3.0全兼容；
? SD I/O： 與SD I/O卡規格版本3.0全兼容，有兩種不同的數據總線模式：1位(默認)和4位（包括SDR和DDR）；
? 104MHz數據傳輸頻率和8位數據傳輸模式；
?中斷和DMA請求；
?數據傳輸支持DDR模式。

SDIO模塊結構框圖如下所示。主要包括以下三個部分：SDIO適配器：由控制單元、命令單元和數據單元組成，控制單元管理時鐘信號，命令單元管理命令的傳輸，數據單元管理數據的傳輸；AHB接口：包括通過AHB總線訪問的寄存器、用于數據傳輸的FIFO單元以及產生中斷和DMA請求信號； 內部DMA（IDMA）以及AHB主機接口 。

SDIO模塊可以實現對SD卡的完全驅動以及協議的實現，包括命令、響應等相關操作，本例程實現使用SDIO驅動SD卡初始化以及讀寫測試等相關操作，具體實現可以參考GD32H7用戶手冊以及代碼解析等。

12.3硬件設計

SD卡相關硬件電路如下圖所示，實驗板上具有SD卡卡座，信號線上有四根數據線，一根CMD命令線以及一根CLK時鐘線，所有信號線通過10K電阻進行上拉，電源地信號線具有10uf以及100nf電容，SD卡插入時，金屬接觸點朝下插入。

12.4代碼解析

12.4.1SDIO初始化配置函數

SDIO初始化配置在sd_io_init（）函數中，其中包括sd_init()初始化、sd_card_information_get（）SD卡信息獲取、sd_card_select_deselect（）SD卡選擇、sd_cardstatus_get（）SD卡狀態獲取、sd_bus_mode_config（）SD卡總線寬度配置以及sd_transfer_mode_config（）SD卡通信模式配置，歷程中選擇了4線查詢模式。

C sd_error_enum sd_io_init(void) { sd_error_enum status = SD_OK; uint32_t cardstate = 0; status = sd_init(); if(SD_OK == status) { status = sd_card_information_get(&sd_cardinfo); } if(SD_OK == status) { status = sd_card_select_deselect(sd_cardinfo.card_rca); } status = sd_cardstatus_get(&cardstate); if(cardstate & 0x02000000) { printf_log("\r\n the card is locked!"); status = sd_lock_unlock(SD_UNLOCK); if(status != SD_OK) { return SD_LOCK_UNLOCK_FAILED; } else { printf_log("\r\n the card is unlocked successfully!"); } } if((SD_OK == status) && (!(cardstate & 0x02000000))) { /* set bus mode */ #if (SDIO_BUSMODE == BUSMODE_4BIT) status = sd_bus_mode_config(SDIO_BUSMODE_4BIT, SDIO_SPEEDMODE); #else status = sd_bus_mode_config(SDIO_BUSMODE_1BIT, SDIO_SPEEDMODE); #endif } #ifdef USE_18V_SWITCH if(SD_OK == status) { /* UHS-I Hosts can perform sampling point tuning using tuning command */ status = sd_tuning(); } #endif /* USE_18V_SWITCH */ if(SD_OK == status) { /* set data transfer mode */ /* if use 1.8V high speed mode, please select the DMA mode */ status = sd_transfer_mode_config(SDIO_DTMODE); } return status; }

12.4.2獲取SD卡信息函數

獲取SD卡信息的函數如下所示，card_info_get（）。

C void card_info_get(void) { uint8_t sd_spec, sd_spec3, sd_spec4, sd_security; uint32_t block_count, block_size; uint16_t temp_ccc; printf_log("\r\n Card information:"); sd_spec = (sd_scr[1] & 0x0F000000) >> 24; sd_spec3 = (sd_scr[1] & 0x00008000) >> 15; sd_spec4 = (sd_scr[1] & 0x00000400) >> 10; if(2 == sd_spec) { if(1 == sd_spec3) { if(1 == sd_spec4) { printf_log("\r\n## Card version 4.xx ##"); } else { printf_log("\r\n## Card version 3.0x ##"); } } else { printf_log("\r\n## Card version 2.00 ##"); } } else if(1 == sd_spec) { printf_log("\r\n## Card version 1.10 ##"); } else if(0 == sd_spec) { printf_log("\r\n## Card version 1.0x ##"); } sd_security = (sd_scr[1] & 0x00700000) >> 20; if(2 == sd_security) { printf_log("\r\n## security v1.01 ##"); } else if(3 == sd_security) { printf_log("\r\n## security v2.00 ##"); } else if(4 == sd_security) { printf_log("\r\n## security v3.00 ##"); } block_count = (sd_cardinfo.card_csd.c_size + 1) * 1024; block_size = 512; printf_log("\r\n## Device size is %dKB ##", sd_card_capacity_get()); printf_log("\r\n## Block size is %dB ##", block_size); printf_log("\r\n## Block count is %d ##", block_count); if(sd_cardinfo.card_csd.read_bl_partial) { printf_log("\r\n## Partial blocks for read allowed ##"); } if(sd_cardinfo.card_csd.write_bl_partial) { printf_log("\r\n## Partial blocks for write allowed ##"); } temp_ccc = sd_cardinfo.card_csd.ccc; printf_log("\r\n## CardCommandClasses is: %x ##", temp_ccc); if((SD_CCC_BLOCK_READ & temp_ccc) && (SD_CCC_BLOCK_WRITE & temp_ccc)) { printf_log("\r\n## Block operation supported ##"); } if(SD_CCC_ERASE & temp_ccc) { printf_log("\r\n## Erase supported ##"); } if(SD_CCC_WRITE_PROTECTION & temp_ccc) { printf_log("\r\n## Write protection supported ##"); } if(SD_CCC_LOCK_CARD & temp_ccc) { printf_log("\r\n## Lock unlock supported ##"); } if(SD_CCC_APPLICATION_SPECIFIC & temp_ccc) { printf_log("\r\n## Application specific supported ##"); } if(SD_CCC_IO_MODE & temp_ccc) { printf_log("\r\n## I/O mode supported ##"); } if(SD_CCC_SWITCH & temp_ccc) { printf_log("\r\n## Switch function supported ##"); } }

12.4.3SD卡數據塊寫入函數

SD卡數據塊寫入函數如下所示，通過該函數可實現SD卡數據塊的數據寫入。

C sd_error_enum sd_block_write(uint32_t *pwritebuffer, uint32_t writeaddr, uint16_t blocksize) { /* initialize the variables */ sd_error_enum status = SD_OK; uint8_t cardstate = 0U; uint32_t count = 0U, align = 0U, datablksize = SDIO_DATABLOCKSIZE_1BYTE, *ptempbuff = pwritebuffer; uint32_t transbytes = 0U, restwords = 0U, response = 0U; __IO uint32_t timeout = 0U; if(NULL == pwritebuffer) { status = SD_PARAMETER_INVALID; return status; } transerror = SD_OK; transend = 0U; totalnumber_bytes = 0U; /* clear all DSM configuration */ sdio_data_config(SDIO, 0U, 0U, SDIO_DATABLOCKSIZE_1BYTE); sdio_data_transfer_config(SDIO, SDIO_TRANSMODE_BLOCKCOUNT, SDIO_TRANSDIRECTION_TOCARD); sdio_dsm_disable(SDIO); sdio_idma_disable(SDIO); /* check whether the card is locked */ if(sdio_response_get(SDIO, SDIO_RESPONSE0) & SD_CARDSTATE_LOCKED) { status = SD_LOCK_UNLOCK_FAILED; return status; } /* blocksize is fixed in 512B for SDHC card */ if(SDIO_HIGH_CAPACITY_SD_CARD != cardtype) { writeaddr *= 512U; } else { blocksize = 512U; } align = blocksize & (blocksize - 1U); if((blocksize > 0U) && (blocksize <= 2048U) && (0U == align)) { datablksize = sd_datablocksize_get(blocksize); /* send CMD16(SET_BLOCKLEN) to set the block length */ sdio_command_response_config(SDIO, SD_CMD_SET_BLOCKLEN, (uint32_t)blocksize, SDIO_RESPONSETYPE_SHORT); sdio_wait_type_set(SDIO, SDIO_WAITTYPE_NO); sdio_csm_enable(SDIO); /* check if some error occurs */ status = r1_error_check(SD_CMD_SET_BLOCKLEN); if(SD_OK != status) { return status; } } else { status = SD_PARAMETER_INVALID; return status; } /* send CMD13(SEND_STATUS), addressed card sends its status registers */ sdio_command_response_config(SDIO, SD_CMD_SEND_STATUS, (uint32_t)sd_rca << SD_RCA_SHIFT, SDIO_RESPONSETYPE_SHORT); sdio_wait_type_set(SDIO, SDIO_WAITTYPE_NO); sdio_csm_enable(SDIO); /* check if some error occurs */ status = r1_error_check(SD_CMD_SEND_STATUS); if(SD_OK != status) { return status; } response = sdio_response_get(SDIO, SDIO_RESPONSE0); timeout = 100000U; while((0U == (response & SD_R1_READY_FOR_DATA)) && (timeout > 0U)) { /* continue to send CMD13 to polling the state of card until buffer empty or timeout */ --timeout; /* send CMD13(SEND_STATUS), addressed card sends its status registers */ sdio_command_response_config(SDIO, SD_CMD_SEND_STATUS, (uint32_t)sd_rca << SD_RCA_SHIFT, SDIO_RESPONSETYPE_SHORT); sdio_wait_type_set(SDIO, SDIO_WAITTYPE_NO); sdio_csm_enable(SDIO); /* check if some error occurs */ status = r1_error_check(SD_CMD_SEND_STATUS); if(SD_OK != status) { return status; } response = sdio_response_get(SDIO, SDIO_RESPONSE0); } if(0U == timeout) { return SD_ERROR; } stopcondition = 0U; totalnumber_bytes = blocksize; /* configure the SDIO data transmisson */ sdio_data_config(SDIO, SD_DATATIMEOUT, totalnumber_bytes, datablksize); sdio_data_transfer_config(SDIO, SDIO_TRANSMODE_BLOCKCOUNT, SDIO_TRANSDIRECTION_TOCARD); sdio_trans_start_enable(SDIO); if(SD_POLLING_MODE == transmode) { /* send CMD24(WRITE_BLOCK) to write a block */ sdio_command_response_config(SDIO, SD_CMD_WRITE_BLOCK, writeaddr, SDIO_RESPONSETYPE_SHORT); sdio_wait_type_set(SDIO, SDIO_WAITTYPE_NO); sdio_csm_enable(SDIO); /* check if some error occurs */ status = r1_error_check(SD_CMD_WRITE_BLOCK); if(SD_OK != status) { return status; } /* polling mode */ while(!sdio_flag_get(SDIO, SDIO_FLAG_DTCRCERR | SDIO_FLAG_DTTMOUT | SDIO_FLAG_TXURE | SDIO_FLAG_DTBLKEND | SDIO_FLAG_DTEND)) { if(RESET != sdio_flag_get(SDIO, SDIO_FLAG_TFH)) { /* at least 8 words can be written into the FIFO */ if((totalnumber_bytes - transbytes) < SD_FIFOHALF_BYTES) { restwords = (totalnumber_bytes - transbytes) / 4U + (((totalnumber_bytes - transbytes) % 4U == 0U) ? 0U : 1U); for(count = 0U; count < restwords; count++) { sdio_data_write(SDIO, *ptempbuff); ++ptempbuff; transbytes += 4U; } } else { for(count = 0U; count < SD_FIFOHALF_WORDS; count++) { sdio_data_write(SDIO, *(ptempbuff + count)); } /* 8 words(32 bytes) has been transferred */ ptempbuff += SD_FIFOHALF_WORDS; transbytes += SD_FIFOHALF_BYTES; } } } sdio_trans_start_disable(SDIO); /* whether some error occurs and return it */ if(RESET != sdio_flag_get(SDIO, SDIO_FLAG_DTCRCERR)) { status = SD_DATA_CRC_ERROR; sdio_flag_clear(SDIO, SDIO_FLAG_DTCRCERR); return status; } else if(RESET != sdio_flag_get(SDIO, SDIO_FLAG_DTTMOUT)) { status = SD_DATA_TIMEOUT; sdio_flag_clear(SDIO, SDIO_FLAG_DTTMOUT); return status; } else if(RESET != sdio_flag_get(SDIO, SDIO_FLAG_TXURE)) { status = SD_TX_UNDERRUN_ERROR; sdio_flag_clear(SDIO, SDIO_FLAG_TXURE); return status; } else { /* if else end */ } } else if(SD_DMA_MODE == transmode) { /* DMA mode */ /* enable the SDIO corresponding interrupts and DMA */ sdio_interrupt_enable(SDIO, SDIO_INT_DTCRCERR | SDIO_INT_DTTMOUT | SDIO_INT_TXURE | SDIO_INT_DTEND); dma_config(pwritebuffer, (uint32_t)(blocksize >> 5)); sdio_idma_enable(SDIO); /* send CMD24(WRITE_BLOCK) to write a block */ sdio_command_response_config(SDIO, SD_CMD_WRITE_BLOCK, writeaddr, SDIO_RESPONSETYPE_SHORT); sdio_wait_type_set(SDIO, SDIO_WAITTYPE_NO); sdio_csm_enable(SDIO); /* check if some error occurs */ status = r1_error_check(SD_CMD_WRITE_BLOCK); if(SD_OK != status) { return status; } while((0U == transend) && (SD_OK == transerror)) { } if(SD_OK != transerror) { return transerror; } } else { status = SD_PARAMETER_INVALID; return status; } /* clear the DATA_FLAGS flags */ sdio_flag_clear(SDIO, SDIO_MASK_DATA_FLAGS); /* get the card state and wait the card is out of programming and receiving state */ status = sd_card_state_get(&cardstate); while((SD_OK == status) && ((SD_CARDSTATE_PROGRAMMING == cardstate) || (SD_CARDSTATE_RECEIVING == cardstate))) { status = sd_card_state_get(&cardstate); } return status; }

12.4.4SD卡數據塊讀取函數

SD卡數據塊讀取函數如下所示。

C sd_error_enum sd_block_read(uint32_t *preadbuffer, uint32_t readaddr, uint16_t blocksize) { /* initialize the variables */ sd_error_enum status = SD_OK; uint32_t count = 0U, align = 0U, datablksize = SDIO_DATABLOCKSIZE_1BYTE, *ptempbuff = preadbuffer; __IO uint32_t timeout = 0U; if(NULL == preadbuffer) { status = SD_PARAMETER_INVALID; return status; } transerror = SD_OK; transend = 0U; totalnumber_bytes = 0U; /* clear all DSM configuration */ sdio_data_config(SDIO, 0U, 0U, SDIO_DATABLOCKSIZE_1BYTE); sdio_data_transfer_config(SDIO, SDIO_TRANSMODE_BLOCKCOUNT, SDIO_TRANSDIRECTION_TOCARD); sdio_dsm_disable(SDIO); sdio_idma_disable(SDIO); /* check whether the card is locked */ if(sdio_response_get(SDIO, SDIO_RESPONSE0) & SD_CARDSTATE_LOCKED) { status = SD_LOCK_UNLOCK_FAILED; return status; } /* blocksize is fixed in 512B for SDHC card */ if(SDIO_HIGH_CAPACITY_SD_CARD != cardtype) { readaddr *= 512U; } else { blocksize = 512U; } align = blocksize & (blocksize - 1U); if((blocksize > 0U) && (blocksize <= 2048U) && (0U == align)) { datablksize = sd_datablocksize_get(blocksize); /* send CMD16(SET_BLOCKLEN) to set the block length */ sdio_command_response_config(SDIO, SD_CMD_SET_BLOCKLEN, (uint32_t)blocksize, SDIO_RESPONSETYPE_SHORT); sdio_wait_type_set(SDIO, SDIO_WAITTYPE_NO); sdio_csm_enable(SDIO); /* check if some error occurs */ status = r1_error_check(SD_CMD_SET_BLOCKLEN); if(SD_OK != status) { return status; } } else { status = SD_PARAMETER_INVALID; return status; } stopcondition = 0U; totalnumber_bytes = (uint32_t)blocksize; if(SD_POLLING_MODE == transmode) { /* configure SDIO data transmisson */ sdio_data_config(SDIO, SD_DATATIMEOUT, totalnumber_bytes, datablksize); sdio_data_transfer_config(SDIO, SDIO_TRANSMODE_BLOCKCOUNT, SDIO_TRANSDIRECTION_TOSDIO); sdio_trans_start_enable(SDIO); /* send CMD17(READ_SINGLE_BLOCK) to read a block */ sdio_command_response_config(SDIO, SD_CMD_READ_SINGLE_BLOCK, (uint32_t)readaddr, SDIO_RESPONSETYPE_SHORT); sdio_wait_type_set(SDIO, SDIO_WAITTYPE_NO); sdio_csm_enable(SDIO); /* check if some error occurs */ status = r1_error_check(SD_CMD_READ_SINGLE_BLOCK); if(SD_OK != status) { return status; } /* polling mode */ while(!sdio_flag_get(SDIO, SDIO_FLAG_DTCRCERR | SDIO_FLAG_DTTMOUT | SDIO_FLAG_RXORE | SDIO_FLAG_DTBLKEND | SDIO_FLAG_DTEND)) { if(RESET != sdio_flag_get(SDIO, SDIO_FLAG_RFH)) { /* at least 8 words can be read in the FIFO */ for(count = 0U; count < SD_FIFOHALF_WORDS; count++) { *(ptempbuff + count) = sdio_data_read(SDIO); } ptempbuff += SD_FIFOHALF_WORDS; } } sdio_trans_start_disable(SDIO); /* whether some error occurs and return it */ if(RESET != sdio_flag_get(SDIO, SDIO_FLAG_DTCRCERR)) { status = SD_DATA_CRC_ERROR; sdio_flag_clear(SDIO, SDIO_FLAG_DTCRCERR); return status; } else if(RESET != sdio_flag_get(SDIO, SDIO_FLAG_DTTMOUT)) { status = SD_DATA_TIMEOUT; sdio_flag_clear(SDIO, SDIO_FLAG_DTTMOUT); return status; } else if(RESET != sdio_flag_get(SDIO, SDIO_FLAG_RXORE)) { status = SD_RX_OVERRUN_ERROR; sdio_flag_clear(SDIO, SDIO_FLAG_RXORE); return status; } else { /* if else end */ } while((SET != sdio_flag_get(SDIO, SDIO_FLAG_RFE)) && (SET == sdio_flag_get(SDIO, SDIO_FLAG_DATSTA))) { *ptempbuff = sdio_data_read(SDIO); ++ptempbuff; } /* clear the DATA_FLAGS flags */ sdio_flag_clear(SDIO, SDIO_MASK_DATA_FLAGS); } else if(SD_DMA_MODE == transmode) { /* DMA mode */ /* enable the SDIO corresponding interrupts and DMA function */ sdio_interrupt_enable(SDIO, SDIO_INT_CCRCERR | SDIO_INT_DTTMOUT | SDIO_INT_RXORE | SDIO_INT_DTEND); dma_config(preadbuffer, (uint32_t)(blocksize >> 5)); sdio_idma_enable(SDIO); /* configure SDIO data transmisson */ sdio_data_config(SDIO, SD_DATATIMEOUT, totalnumber_bytes, datablksize); sdio_data_transfer_config(SDIO, SDIO_TRANSMODE_BLOCKCOUNT, SDIO_TRANSDIRECTION_TOSDIO); sdio_trans_start_enable(SDIO); /* send CMD17(READ_SINGLE_BLOCK) to read a block */ sdio_command_response_config(SDIO, SD_CMD_READ_SINGLE_BLOCK, (uint32_t)readaddr, SDIO_RESPONSETYPE_SHORT); sdio_wait_type_set(SDIO, SDIO_WAITTYPE_NO); sdio_csm_enable(SDIO); /* check if some error occurs */ status = r1_error_check(SD_CMD_READ_SINGLE_BLOCK); if(SD_OK != status) { return status; } while((0U == transend) && (SD_OK == transerror)) { } if(SD_OK != transerror) { return transerror; } } else { status = SD_PARAMETER_INVALID; } return status; }

12.4.5SD卡lock和unlock配置函數

SD卡lock和unlock配置函數如下所示。通過形參實現對SD卡的lock和unlock，若希望lock SD卡，lcokstate配置為SD_LOCK；若希望unlock SD卡，lockstate配置為SD_UNLOCK.

C sd_error_enum sd_lock_unlock(uint8_t lockstate) { sd_error_enum status = SD_OK; uint8_t cardstate = 0U, tempbyte = 0U; uint32_t pwd1 = 0U, pwd2 = 0U, response = 0U, timeout = 0U; uint16_t tempccc = 0U; /* get the card command classes from CSD */ tempbyte = (uint8_t)((sd_csd[1] & SD_MASK_24_31BITS) >> 24U); tempccc = ((uint16_t)tempbyte << 4U); tempbyte = (uint8_t)((sd_csd[1] & SD_MASK_16_23BITS) >> 16U); tempccc |= (((uint16_t)tempbyte & 0xF0U) >> 4U); if(0U == (tempccc & SD_CCC_LOCK_CARD)) { /* don't support the lock command */ status = SD_FUNCTION_UNSUPPORTED; return status; } /* password pattern */ pwd1 = (0x01020600U | lockstate); pwd2 = 0x03040506U; /* clear all DSM configuration */ sdio_data_config(SDIO, 0U, 0U, SDIO_DATABLOCKSIZE_1BYTE); sdio_data_transfer_config(SDIO, SDIO_TRANSMODE_BLOCKCOUNT, SDIO_TRANSDIRECTION_TOCARD); sdio_dsm_disable(SDIO); sdio_idma_disable(SDIO); /* send CMD16(SET_BLOCKLEN) to set the block length */ sdio_command_response_config(SDIO, SD_CMD_SET_BLOCKLEN, (uint32_t)8U, SDIO_RESPONSETYPE_SHORT); sdio_wait_type_set(SDIO, SDIO_WAITTYPE_NO); sdio_csm_enable(SDIO); /* check if some error occurs */ status = r1_error_check(SD_CMD_SET_BLOCKLEN); if(SD_OK != status) { return status; } /* send CMD13(SEND_STATUS), addressed card sends its status register */ sdio_command_response_config(SDIO, SD_CMD_SEND_STATUS, (uint32_t)sd_rca << SD_RCA_SHIFT, SDIO_RESPONSETYPE_SHORT); sdio_wait_type_set(SDIO, SDIO_WAITTYPE_NO); sdio_csm_enable(SDIO); /* check if some error occurs */ status = r1_error_check(SD_CMD_SEND_STATUS); if(SD_OK != status) { return status; } response = sdio_response_get(SDIO, SDIO_RESPONSE0); timeout = 100000U; while((0U == (response & SD_R1_READY_FOR_DATA)) && (timeout > 0U)) { /* continue to send CMD13 to polling the state of card until buffer empty or timeout */ --timeout; /* send CMD13(SEND_STATUS), addressed card sends its status registers */ sdio_command_response_config(SDIO, SD_CMD_SEND_STATUS, (uint32_t)sd_rca << SD_RCA_SHIFT, SDIO_RESPONSETYPE_SHORT); sdio_wait_type_set(SDIO, SDIO_WAITTYPE_NO); sdio_csm_enable(SDIO); /* check if some error occurs */ status = r1_error_check(SD_CMD_SEND_STATUS); if(SD_OK != status) { return status; } response = sdio_response_get(SDIO, SDIO_RESPONSE0); } if(0U == timeout) { status = SD_ERROR; return status; } /* send CMD42(LOCK_UNLOCK) to set/reset the password or lock/unlock the card */ sdio_command_response_config(SDIO, SD_CMD_LOCK_UNLOCK, (uint32_t)0x0, SDIO_RESPONSETYPE_SHORT); sdio_wait_type_set(SDIO, SDIO_WAITTYPE_NO); sdio_csm_enable(SDIO); /* check if some error occurs */ status = r1_error_check(SD_CMD_LOCK_UNLOCK); if(SD_OK != status) { return status; } response = sdio_response_get(SDIO, SDIO_RESPONSE0); /* configure the SDIO data transmisson */ sdio_data_config(SDIO, SD_DATATIMEOUT, (uint32_t)8, SDIO_DATABLOCKSIZE_8BYTES); sdio_data_transfer_config(SDIO, SDIO_TRANSMODE_BLOCKCOUNT, SDIO_TRANSDIRECTION_TOCARD); sdio_dsm_enable(SDIO); /* write password pattern */ sdio_data_write(SDIO, pwd1); sdio_data_write(SDIO, pwd2); /* whether some error occurs and return it */ if(RESET != sdio_flag_get(SDIO, SDIO_FLAG_DTCRCERR)) { status = SD_DATA_CRC_ERROR; sdio_flag_clear(SDIO, SDIO_FLAG_DTCRCERR); return status; } else if(RESET != sdio_flag_get(SDIO, SDIO_FLAG_DTTMOUT)) { status = SD_DATA_TIMEOUT; sdio_flag_clear(SDIO, SDIO_FLAG_DTTMOUT); return status; } else if(RESET != sdio_flag_get(SDIO, SDIO_FLAG_TXURE)) { status = SD_TX_UNDERRUN_ERROR; sdio_flag_clear(SDIO, SDIO_FLAG_TXURE); return status; } else { /* if else end */ } /* clear the SDIO_INTC flags */ sdio_flag_clear(SDIO, SDIO_MASK_INTC_FLAGS); /* get the card state and wait the card is out of programming and receiving state */ status = sd_card_state_get(&cardstate); while((SD_OK == status) && ((SD_CARDSTATE_PROGRAMMING == cardstate) || (SD_CARDSTATE_RECEIVING == cardstate))) { status = sd_card_state_get(&cardstate); } return status; }

12.4.6SD卡erase擦除操作函數

SD卡擦除操作函數如下，其形參為擦除起始地址以及結束地址。

C sd_error_enum sd_erase(uint32_t startaddr, uint32_t endaddr) { /* initialize the variables */ sd_error_enum status = SD_OK; uint32_t count = 0U, clkdiv = 0U; __IO uint32_t delay = 0U; uint8_t cardstate = 0U, tempbyte = 0U; uint16_t tempccc = 0U; /* get the card command classes from CSD */ tempbyte = (uint8_t)((sd_csd[1] & SD_MASK_24_31BITS) >> 24U); tempccc = (uint16_t)((uint16_t)tempbyte << 4U); tempbyte = (uint8_t)((sd_csd[1] & SD_MASK_16_23BITS) >> 16U); tempccc |= ((uint16_t)tempbyte & 0xF0U) >> 4U; if(0U == (tempccc & SD_CCC_ERASE)) { /* don't support the erase command */ status = SD_FUNCTION_UNSUPPORTED; return status; } clkdiv = (SDIO_CLKCTL(SDIO) & SDIO_CLKCTL_DIV); clkdiv *= 2U; delay = 168000U / clkdiv; /* check whether the card is locked */ if(sdio_response_get(SDIO, SDIO_RESPONSE0) & SD_CARDSTATE_LOCKED) { status = SD_LOCK_UNLOCK_FAILED; return(status); } /* blocksize is fixed in 512B for SDHC card */ if(SDIO_HIGH_CAPACITY_SD_CARD != cardtype) { startaddr *= 512U; endaddr *= 512U; } if((SDIO_STD_CAPACITY_SD_CARD_V1_1 == cardtype) || (SDIO_STD_CAPACITY_SD_CARD_V2_0 == cardtype) || (SDIO_HIGH_CAPACITY_SD_CARD == cardtype)) { /* send CMD32(ERASE_WR_BLK_START) to set the address of the first write block to be erased */ sdio_command_response_config(SDIO, SD_CMD_ERASE_WR_BLK_START, startaddr, SDIO_RESPONSETYPE_SHORT); sdio_wait_type_set(SDIO, SDIO_WAITTYPE_NO); sdio_csm_enable(SDIO); /* check if some error occurs */ status = r1_error_check(SD_CMD_ERASE_WR_BLK_START); if(SD_OK != status) { return status; } /* send CMD33(ERASE_WR_BLK_END) to set the address of the last write block of the continuous range to be erased */ sdio_command_response_config(SDIO, SD_CMD_ERASE_WR_BLK_END, endaddr, SDIO_RESPONSETYPE_SHORT); sdio_wait_type_set(SDIO, SDIO_WAITTYPE_NO); sdio_csm_enable(SDIO); /* check if some error occurs */ status = r1_error_check(SD_CMD_ERASE_WR_BLK_END); if(SD_OK != status) { return status; } } /* send CMD38(ERASE) to set the address of the first write block to be erased */ sdio_command_response_config(SDIO, SD_CMD_ERASE, (uint32_t)0x0, SDIO_RESPONSETYPE_SHORT); sdio_wait_type_set(SDIO, SDIO_WAITTYPE_NO); sdio_csm_enable(SDIO); /* check if some error occurs */ status = r1_error_check(SD_CMD_ERASE); if(SD_OK != status) { return status; } /* loop until the counter is reach to the calculated time */ for(count = 0U; count < delay; count++) { } /* get the card state and wait the card is out of programming and receiving state */ status = sd_card_state_get(&cardstate); while((SD_OK == status) && ((SD_CARDSTATE_PROGRAMMING == cardstate) || (SD_CARDSTATE_RECEIVING == cardstate))) { status = sd_card_state_get(&cardstate); } return status; }

12.4.7主函數

SD卡主函數如下，可實現對SD卡的擦寫讀以及加鎖解鎖操作。

C int main() { sd_error_enum sd_error; Drv_Err state = DRV_ERROR; uint16_t i = 5; #ifdef DATA_PRINT uint8_t *pdata; #endif /* DATA_PRINT */ /* enable the CPU Cache */ driver_init(); /* configure the NVIC and USART */ nvic_config(); bsp_led_group_init(); /* turn off all the LEDs */ bsp_led_off(&LED1); bsp_led_off(&LED2); /* initialize the card */ do { sd_error = sd_io_init(); } while((SD_OK != sd_error) && (--i)); if(i) { printf_log("\r\n Card init success!\r\n"); } else { printf_log("\r\n Card init failed!\r\n"); /* turn on LED1, LED2 */ bsp_led_on(&LED1); bsp_led_on(&LED2); while(1) { } } /* get the information of the card and print it out by USART */ card_info_get(); /* init the write buffer */ for(i = 0; i < 512; i++) { buf_write[i] = i; } /* clean and invalidate buffer in D-Cache */ SCB_CleanInvalidateDCache_by_Addr(buf_write, 512 * 4); printf_log("\r\n\r\n Card test:"); /* single block operation test */ sd_error = sd_block_write(buf_write, 100, 512); if(SD_OK != sd_error) { printf_log("\r\n Block write fail!"); /* turn on LED1, LED2 */ bsp_led_on(&LED1); bsp_led_on(&LED2); while(1) { } } else { printf_log("\r\n Block write success!"); } sd_error = sd_block_read(buf_read, 100, 512); if(SD_OK != sd_error) { printf_log("\r\n Block read fail!"); /* turn on LED1, LED2 */ bsp_led_on(&LED1); bsp_led_on(&LED2); while(1) { } } else { printf_log("\r\n Block read success!"); #ifdef DATA_PRINT SCB_CleanInvalidateDCache_by_Addr(buf_read, 512 * 4); pdata = (uint8_t *)buf_read; /* print data by USART */ printf_log("\r\n"); for(i = 0; i < 128; i++) { printf_log(" %3d %3d %3d %3d ", *pdata, *(pdata + 1), *(pdata + 2), *(pdata + 3)); pdata += 4; if(0 == (i + 1) % 4) { printf_log("\r\n"); } } #endif /* DATA_PRINT */ } /* compare the write date and the read data */ state = memory_compare((uint8_t *)buf_write, (uint8_t *)buf_read, 128*4); if(SUCCESS == state) { printf_log("\r\n Single block read compare successfully!"); } else { printf_log("\r\n Single block read compare fail!"); /* turn on LED1, LED2 */ bsp_led_on(&LED1); bsp_led_on(&LED2); while(1) { } } /* lock and unlock operation test */ if(SD_CCC_LOCK_CARD & sd_cardinfo.card_csd.ccc) { /* lock the card */ sd_error = sd_lock_unlock(SD_LOCK); if(SD_OK != sd_error) { printf_log("\r\n Lock failed!"); /* turn on LED1, LED2 */ bsp_led_on(&LED1); bsp_led_on(&LED2); while(1) { } } else { printf_log("\r\n The card is locked!"); } sd_error = sd_erase(100, 101); if(SD_OK != sd_error) { printf_log("\r\n Erase failed!"); } else { printf_log("\r\n Erase success!"); } /* unlock the card */ sd_error = sd_lock_unlock(SD_UNLOCK); if(SD_OK != sd_error) { printf_log("\r\n Unlock failed!"); /* turn on LED1, LED2 */ bsp_led_on(&LED1); bsp_led_on(&LED2); while(1) { } } else { printf_log("\r\n The card is unlocked!"); } sd_error = sd_erase(100, 101); if(SD_OK != sd_error) { printf_log("\r\n Erase failed!"); } else { printf_log("\r\n Erase success!"); } sd_error = sd_block_read(buf_read, 100, 512); if(SD_OK != sd_error) { printf_log("\r\n Block read fail!"); /* turn on LED1, LED2 */ bsp_led_on(&LED1); bsp_led_on(&LED2); while(1) { } } else { printf_log("\r\n Block read success!"); #ifdef DATA_PRINT SCB_CleanInvalidateDCache_by_Addr(buf_read, 512 * 4); pdata = (uint8_t *)buf_read; /* print data by USART */ printf_log("\r\n"); for(i = 0; i < 128; i++) { printf_log(" %3d %3d %3d %3d ", *pdata, *(pdata + 1), *(pdata + 2), *(pdata + 3)); pdata += 4; if(0 == (i + 1) % 4) { printf_log("\r\n"); } } #endif /* DATA_PRINT */ } } /* multiple blocks operation test */ sd_error = sd_multiblocks_write(buf_write, 200, 512, 3); if(SD_OK != sd_error) { printf_log("\r\n Multiple block write fail!"); /* turn on LED1, LED2 */ bsp_led_on(&LED1); bsp_led_on(&LED2); while(1) { } } else { printf_log("\r\n Multiple block write success!"); } sd_error = sd_multiblocks_read(buf_read, 200, 512, 3); if(SD_OK != sd_error) { printf_log("\r\n Multiple block read fail!"); /* turn on LED1, LED2 */ bsp_led_on(&LED1); bsp_led_on(&LED2); while(1) { } } else { printf_log("\r\n Multiple block read success!"); #ifdef DATA_PRINT SCB_CleanInvalidateDCache_by_Addr(buf_read, 512 * 4); pdata = (uint8_t *)buf_read; /* print data by USART */ printf_log("\r\n"); for(i = 0; i < 512; i++) { printf_log(" %3d %3d %3d %3d ", *pdata, *(pdata + 1), *(pdata + 2), *(pdata + 3)); pdata += 4; if(0 == (i + 1) % 4) { printf_log("\r\n"); } } #endif /* DATA_PRINT */ } /* compare the write date and the read data */ state = memory_compare((uint8_t *)buf_write, (uint8_t *)buf_read, 128*3*4); if(SUCCESS == state) { printf_log("\r\n Multiple block read compare successfully!"); } else { printf_log("\r\n Multiple block read compare fail!"); /* turn on LED1, LED2 */ bsp_led_on(&LED1); bsp_led_on(&LED2); while(1) { } } printf_log("\r\n SD card test successfully!"); while(1) {}; }

12.5實驗結果

將SD卡讀寫實驗例程燒錄到海棠派開發板中，并在卡槽中插入SD卡，在液晶屏上，將會觀察到SD卡相關操作結果。

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