Arduino.ru

Есть такая библиотека FatFS для использования SD карт (http://elm-chan.org/fsw/ff/00index_e.html).

В библиотеке есть примеры использования, в которых просят заполнить поля для подстановки своих портов и функций. Что я сделал следующим образом (https://cadlab.io/project/24804/master/files/send_code/mmc_avr_spi.c). 

// mmc_avr_spi.c
#include <avr/io.h>
#include <avr/interrupt.h> 
#include "diskio.h"
#include "mmc_avr.h"

/* AtMega328p 
PB2  --  CS     (Chip Select - Select Slave)
PB3  --  MOSI   (Output from master to slave)
PB4  --  MISO   (Input from slave to master)
PB5  --  SCK    (SPI Bus Master clock Input to slave))
*/
#define  CS     PB2 
#define  MOSI   PB3
#define  MISO   PB4
#define  SCLK   PB5 

/* Peripheral controls (Platform dependent) */
#define CS_LOW()	PORTB &= ~(1 <<CS) /* Set CS (Chip Select = Slave Select (SS)) low */
#define	CS_HIGH()	PORTB |=  (1 <<CS)	/* Set CS high */
#define MMC_CD		1 // Test if card detected. yes:true, no:false, default:true 
#define MMC_WP		0                         // Write Lock enable. (yes true , no false, default: false)

/*--------------------------------------------------------------------------

   Module Private Functions

---------------------------------------------------------------------------*/

/* Definitions for MMC/SDC command */
#define CMD0	(0)			/* GO_IDLE_STATE */
#define CMD1	(1)			/* SEND_OP_COND (MMC) */
#define	ACMD41	(0x80+41)	/* SEND_OP_COND (SDC) */
#define CMD8	(8)			/* SEND_IF_COND */
#define CMD9	(9)			/* SEND_CSD */
#define CMD10	(10)		/* SEND_CID */
#define CMD12	(12)		/* STOP_TRANSMISSION */
#define ACMD13	(0x80+13)	/* SD_STATUS (SDC) */
#define CMD16	(16)		/* SET_BLOCKLEN */
#define CMD17	(17)		/* READ_SINGLE_BLOCK */
#define CMD18	(18)		/* READ_MULTIPLE_BLOCK */
#define CMD23	(23)		/* SET_BLOCK_COUNT (MMC) */
#define	ACMD23	(0x80+23)	/* SET_WR_BLK_ERASE_COUNT (SDC) */
#define CMD24	(24)		/* WRITE_BLOCK */
#define CMD25	(25)		/* WRITE_MULTIPLE_BLOCK */
#define CMD32	(32)		/* ERASE_ER_BLK_START */
#define CMD33	(33)		/* ERASE_ER_BLK_END */
#define CMD38	(38)		/* ERASE */
#define	CMD48	(48)		/* READ_EXTR_SINGLE */
#define	CMD49	(49)		/* WRITE_EXTR_SINGLE */
#define CMD55	(55)		/* APP_CMD */
#define CMD58	(58)		/* READ_OCR */

static volatile DSTATUS Stat = STA_NOINIT;	/* Disk status */

/* 100Hz decrement timers */
static volatile BYTE Timer1;
static volatile UINT Timer2;

static BYTE CardType;			/* Card type flags (b0:MMC, b1:SDv1, b2:SDv2, b3:Block addressing) */

/*-----------------------------------------------------------------------*/
/* Power Control  (Platform dependent)                                   */
/*-----------------------------------------------------------------------*/
/* When the target system does not support socket power control, there   */
/* is nothing to do in these functions and chk_power always returns 1.   */

#define	FCLK_SLOW()	    SPCR |=   (1 << SPR1)|(1 << SPR0);  SPSR &= ~(1 << SPI2X);	/* Set SPI slow clock (100-400kHz) */
#define	FCLK_FAST()	    SPCR &= ~((1 << SPR1)|(1 << SPR0)); SPSR |=  (1 << SPI2X); /* Set SPI fast clock (20MHz max) */

static
void power_on (void)
{
   	/* Configure MOSI/MISO/SCLK/CS pins for SPI */
    DDRB |= (1 << CS);	    // Output -CS 
    DDRB |= (1 << SCLK);	// Output - CLK
    DDRB |= (1 << MOSI);	// Output - MOSI
    DDRB &=~(1 << MISO);	// Input -  MISO

	PORTB |= (1 <<CS);  // set HIGH --  (Chip Select) 

	/* Enable SPI module in SPI mode 0 */
        SPCR = (1 << SPE)|(1 << MSTR); // 1 - enable SPI, Master

	// Wait for 100 ms 
	Timer2 = 10;
	while (Timer2);

	FCLK_SLOW();
}

static
void power_off (void)
{
	/* Disable SPI function */
        SPCR = 0;  

	/* De-configure MOSI/MISO/SCLK/CS pins (set hi-z) */
	DDRB &= ~(1 << CS);		    // Input - CS0
	DDRB &= ~(1 << SCLK);		// Input - CLK
	DDRB &= ~(1 << MOSI);		// Input - MOSI
	DDRB &= ~(1 << MISO);		// Input - MISO
	
	// Disable pull ups on MISO 
	PORTB &= ~(1 << MISO);
}

// mmc_avr_spi.c далее стандартные функции отправки и чтения. 

Полный код теста https://cadlab.io/project/24804/master/files/send_code/ Откуда можно скачать все файлы (Dowloads Files). 

main.c -  f_mount() проходит нормально, но при попытке открыть файл "TEST.TXT", который уже есть на карте, тест постоянно выдаёт ошибку (3) - диск не работает. Может кто использовал эту библиотеку? Что не так?

#include <stdio.h>
#include "uart.h"
#include "ff.h"

const char *errors[] = {
	"(0) Succeeded",
	"(1) A hard error occurred in the low level disk I/O layer",
	"(2) Assertion failed",
	"(3) The physical drive cannot work",
	"(4) Could not find the file",
	"(5) Could not find the path",
	"(6) The path name format is invalid",
	"(7) Access denied due to prohibited access or directory full",
	"(8) Access denied due to prohibited access",
	"(9) The file/directory object is invalid",
	"(10) The physical drive is write protected",
	"(11) The logical drive number is invalid",
	"(12) The volume has no work area",
	"(13) There is no valid FAT volume",
	"(14) The f_mkfs() aborted due to any problem",
	"(15) Could not get a grant to access the volume within defined period",
	"(16) The operation is rejected according to the file sharing policy",
	"(17) LFN working buffer could not be allocated",
	"(18) Number of open files > FF_FS_LOCK",
	"(19) Given parameter is invalid"
};

void die (FRESULT rf) {
    printf("error: %d, %s\n", rf, errors[rf]);
    for(;;);
}

int main (void)
{
    FRESULT fr;
    FATFS fs;
    FIL fil;

    uart_init();   

    /* Open or create a log file and ready to append */
    printf("mount: ");
    fr = f_mount(&fs, "", 0);
    if (fr != FR_OK) 
        die(fr);
    puts ("ok.");

    printf("open:");
    fr = f_open (&fil, "TEST.TXT", FA_READ);    /* Open or create a file */ //|FA_WRITE
    if (fr != FR_OK) 
        die(fr);
    puts("ok.");

    for (;;);
    return 0;
}

Где ошибка?