mmc.i

This is the latest VS1053B chip interface routines combined with Elm Chan s FatFs library. Whole cod

	PORTB = 0b10110101;			/* Enable drivers */
	DDRB  = 0b11000111;
        SPCR = 0b01010000;			/* Initialize SPI port (Mode 0) */
	SPSR = 0b00000001;
}

static
void power_off (void)
{
	PORTB.0 = 0		;				/* Wait for card ready */
	wait_ready();
	release_spi();

	SPCR = 0;				/* Disable SPI function */
	DDRB  = 0b11000000;		/* Disable drivers */
	PORTB = 0b10110000;
	PORTE |=  0x80;			/* Socket power OFF */
	Stat |= 0x01	;		/* Set STA_NOINIT */
}

static
int chk_power(void)		/* Socket power state: 0=off, 1=on */
{
	return (PORTE & 0x80) ? 0 : 1;
}



/*-----------------------------------------------------------------------*/
/* Receive a data packet from MMC                                        */
/*-----------------------------------------------------------------------*/

static
BOOL rcvr_datablock (
	BYTE *buff,			/* Data buffer to store received data */
	UINT btr			/* Byte count (must be multiple of 4) */
)
{
	BYTE token;


	Timer1 = 10;
	do {							/* Wait for data packet in timeout of 100ms */
		token = rcvr_spi();
	} while ((token == 0xFF) && Timer1);
	if(token != 0xFE) return 0;	/* If not valid data token, retutn with error */

	do {							/* Receive the data block into buffer */
		SPDR=0xFF; while(SPSR.7 == 0);; *(buff++)=SPDR;
		SPDR=0xFF; while(SPSR.7 == 0);; *(buff++)=SPDR;
		SPDR=0xFF; while(SPSR.7 == 0);; *(buff++)=SPDR;
		SPDR=0xFF; while(SPSR.7 == 0);; *(buff++)=SPDR;
	} while (btr -= 4);
	rcvr_spi();						/* Discard CRC */
	rcvr_spi();

	return 1;					/* Return with success */
}



/*-----------------------------------------------------------------------*/
/* Send a data packet to MMC                                             */
/*-----------------------------------------------------------------------*/

static
BOOL xmit_datablock (
	const BYTE *buff,	/* 512 byte data block to be transmitted */
	BYTE token			/* Data/Stop token */
)
{
	BYTE resp, wc;


	if (wait_ready() != 0xFF) return 0;

	SPDR=(token); while(SPSR.7 == 0);;					/* Xmit data token */
	if (token != 0xFD) {	/* Is data token */
		wc = 0;
		do {							/* Xmit the 512 byte data block to MMC */
			SPDR=(*buff++); while(SPSR.7 == 0);;
			SPDR=(*buff++); while(SPSR.7 == 0);;
		} while (--wc);
		SPDR=(0xFF); while(SPSR.7 == 0);;					/* CRC (Dummy) */
		SPDR=(0xFF); while(SPSR.7 == 0);;
		resp = rcvr_spi();				/* Reveive data response */
		if ((resp & 0x1F) != 0x05)		/* If not accepted, return with error */
			return 0;
	}

	return 1;
}



/*-----------------------------------------------------------------------*/
/* Send a command packet to MMC                                          */
/*-----------------------------------------------------------------------*/

static
BYTE send_cmd (
	BYTE cmd,		/* Command byte */
	DWORD arg		/* Argument */
)
{
	BYTE n, res;


	if (cmd & 0x80) {	/* ACMD<n> is the command sequense of CMD55-CMD<n> */
		cmd &= 0x7F;
		res = send_cmd((0x40+55)	, 0);
		if (res > 1) return res;
	}

	/* Select the card and wait for ready */
	PORTB.0 = 1		;
	PORTB.0 = 0		;
	if (wait_ready() != 0xFF) return 0xFF;

	/* Send command packet */
	SPDR=(cmd); while(SPSR.7 == 0);;						/* Start + Command index */
	SPDR=((BYTE)(arg >> 24)); while(SPSR.7 == 0);;		/* Argument[31..24] */
	SPDR=((BYTE)(arg >> 16)); while(SPSR.7 == 0);;		/* Argument[23..16] */
	SPDR=((BYTE)(arg >> 8)); while(SPSR.7 == 0);;			/* Argument[15..8] */
	SPDR=((BYTE)arg); while(SPSR.7 == 0);;				/* Argument[7..0] */
	n = 0x01;							/* Dummy CRC + Stop */
	if (cmd == (0x40+0)	) n = 0x95;			/* Valid CRC for CMD0(0) */
	if (cmd == (0x40+8)	) n = 0x87;			/* Valid CRC for CMD8(0x1AA) */
	SPDR=(n); while(SPSR.7 == 0);;

	/* Receive command response */
	if (cmd == (0x40+12)	) rcvr_spi();		/* Skip a stuff byte when stop reading */
	n = 10;								/* Wait for a valid response in timeout of 10 attempts */
	do
		res = rcvr_spi();
	while ((res & 0x80) && --n);

	return res;			/* Return with the response value */
}



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

   Public Functions

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


/*-----------------------------------------------------------------------*/
/* Initialize Disk Drive                                                 */
/*-----------------------------------------------------------------------*/

DSTATUS disk_initialize (
	BYTE drv		/* Physical drive nmuber (0) */
)
{
	BYTE n, cmd, ty, ocr[4];
        

	if (drv) return 0x01	;			/* Supports only single drive */
	if (Stat & 0x02	) return Stat;	/* No card in the socket */

	power_on();							/* Force socket power on */
        
        for (n = 10; n; n--) rcvr_spi();	/* 80 dummy clocks */

	ty = 0;
	if (send_cmd((0x40+0)	, 0) == 1) {			/* Enter Idle state */
		Timer1 = 100;						/* Initialization timeout of 1000 msec */
		if (send_cmd((0x40+8)	, 0x1AA) == 1) {	/* SDHC */
			for (n = 0; n < 4; n++) ocr[n] = rcvr_spi();		/* Get trailing return value of R7 resp */
			if (ocr[2] == 0x01 && ocr[3] == 0xAA) {				/* The card can work at vdd range of 2.7-3.6V */
				while (Timer1 && send_cmd((0xC0+41)	, 1UL << 30));	/* Wait for leaving idle state (ACMD41 with HCS bit) */
				if (Timer1 && send_cmd((0x40+58)	, 0) == 0) {		/* Check CCS bit in the OCR */
					for (n = 0; n < 4; n++) ocr[n] = rcvr_spi();
					ty = (ocr[0] & 0x40) ? 12 : 4;
				}
			}
		} else {							/* SDSC or MMC */
			if (send_cmd((0xC0+41)	, 0) <= 1) 	{
				ty = 2; cmd = (0xC0+41)	;	/* SDSC */
			} else {
				ty = 1; cmd = (0x40+1)	;		/* MMC */
			}
			while (Timer1 && send_cmd(cmd, 0));			/* Wait for leaving idle state */
			if (!Timer1 || send_cmd((0x40+16)	, 512) != 0)	/* Set R/W block length to 512 */
				ty = 0;
		}
	}
	CardType = ty;
	release_spi();

	if (ty) {			/* Initialization succeded */
		Stat &= ~0x01	;		/* Clear STA_NOINIT */
	} else {			/* Initialization failed */
		power_off();
	}

	return Stat;
}



/*-----------------------------------------------------------------------*/
/* Get Disk Status                                                       */
/*-----------------------------------------------------------------------*/

DSTATUS disk_status (
	BYTE drv		/* Physical drive nmuber (0) */
)
{
	if (drv) return 0x01	;		/* Supports only single drive */
	return Stat;
}



/*-----------------------------------------------------------------------*/
/* Read Sector(s)                                                        */
/*-----------------------------------------------------------------------*/

DRESULT disk_read (
	BYTE drv,			/* Physical drive nmuber (0) */
	BYTE *buff,			/* Pointer to the data buffer to store read data */
	DWORD sector,		/* Start sector number (LBA) */
	BYTE count			/* Sector count (1..255) */
)
{
	if (drv || !count) return RES_PARERR;
	if (Stat & 0x01	) return RES_NOTRDY;

	if (!(CardType & 8)) sector *= 512;	/* Convert to byte address if needed */

	if (count == 1) {	/* Single block read */
		if ((send_cmd((0x40+17)	, sector) == 0)	/* READ_SINGLE_BLOCK */
			&& rcvr_datablock(buff, 512))
			count = 0;
	}
	else {				/* Multiple block read */
		if (send_cmd((0x40+18)	, sector) == 0) {	/* READ_MULTIPLE_BLOCK */
			do {
				if (!rcvr_datablock(buff, 512)) break;
				buff += 512;
			} while (--count);
			send_cmd((0x40+12)	, 0);				/* STOP_TRANSMISSION */
		}
	}
	release_spi();

	return count ? RES_ERROR : RES_OK;
}



/*-----------------------------------------------------------------------*/
/* Write Sector(s)                                                       */
/*-----------------------------------------------------------------------*/

DRESULT disk_write (
	BYTE drv,			/* Physical drive nmuber (0) */
	const BYTE *buff,	/* Pointer to the data to be written */
	DWORD sector,		/* Start sector number (LBA) */
	BYTE count			/* Sector count (1..255) */
)
{
	if (drv || !count) return RES_PARERR;
	if (Stat & 0x01	) return RES_NOTRDY;
	if (Stat & 0x04	) return RES_WRPRT;

	if (!(CardType & 8)) sector *= 512;	/* Convert to byte address if needed */

	if (count == 1) {	/* Single block write */
		if ((send_cmd((0x40+24)	, sector) == 0)	/* WRITE_BLOCK */
			&& xmit_datablock(buff, 0xFE))
			count = 0;
	}
	else {				/* Multiple block write */
		if (CardType & 6) send_cmd((0xC0+23)	, count);
		if (send_cmd((0x40+25)	, sector) == 0) {	/* WRITE_MULTIPLE_BLOCK */
			do {
				if (!xmit_datablock(buff, 0xFC)) break;
				buff += 512;
			} while (--count);
			if (!xmit_datablock(0, 0xFD))	/* STOP_TRAN token */
				count = 1;
		}
	}
	release_spi();

	return count ? RES_ERROR : RES_OK;
}



/*-----------------------------------------------------------------------*/
/* Miscellaneous Functions                                               */
/*-----------------------------------------------------------------------*/

DRESULT disk_ioctl (
	BYTE drv,		/* Physical drive nmuber (0) */
	BYTE ctrl,		/* Control code */
	void *buff		/* Buffer to send/receive control data */
)
{
	DRESULT res;
	BYTE n, csd[16], *ptr = buff;
	WORD csize;


	if (drv) return RES_PARERR;

	res = RES_ERROR;

	if (ctrl == 4) {
		switch (*ptr) {
		case 0:		/* Sub control code == 0 (POWER_OFF) */
			if (chk_power())
			power_off();		/* Power off */
			res = RES_OK;
			break;
		case 1:		/* Sub control code == 1 (POWER_ON) */
			power_on();				/* Power on */
			res = RES_OK;
			break;
		case 2:		/* Sub control code == 2 (POWER_GET) */
			*(ptr+1) = (BYTE)chk_power();
			res = RES_OK;
			break;
		default :
			res = RES_PARERR;
		}
	}
	else {
		if (Stat & 0x01	) return RES_NOTRDY;

		switch (ctrl) {
		case 0	 :		/* Make sure that no pending write process */
			PORTB.0 = 0		;
			if (wait_ready() == 0xFF)
				res = RES_OK;
			break;

		case 1	 :	/* Get number of sectors on the disk (DWORD) */
			if ((send_cmd((0x40+9)	, 0) == 0) && rcvr_datablock(csd, 16)) {
				if ((csd[0] >> 6) == 1) {	/* SDC ver 2.00 */
					csize = csd[9] + ((WORD)csd[8] << 8) + 1;
					*(DWORD*)buff = (DWORD)csize << 10;
				} else {					/* SDC ver 1.XX or MMC*/
					n = (csd[5] & 15) + ((csd[10] & 128) >> 7) + ((csd[9] & 3) << 1) + 2;
					csize = (csd[8] >> 6) + ((WORD)csd[7] << 2) + ((WORD)(csd[6] & 3) << 10) + 1;
					*(DWORD*)buff = (DWORD)csize << (n - 9);
				}
				res = RES_OK;
			}
			break;

		case 2 :	/* Get R/W sector size (WORD) */
			*(WORD*)buff = 512;
			res = RES_OK;
			break;

		case 3	 :	/* Get erase block size in unit of sector (DWORD) */
			if (CardType & 4) {			/* SDC ver 2.00 */
				if (send_cmd((0xC0+13)	, 0) == 0) {		/* Read SD status */
					rcvr_spi();
					if (rcvr_datablock(csd, 16)) {				/* Read partial block */
						for (n = 64 - 16; n; n--) rcvr_spi();	/* Purge trailing data */
						*(DWORD*)buff = 16UL << (csd[10] >> 4);
						res = RES_OK;
					}
				}
			} else {					/* SDC ver 1.XX or MMC */
				if ((send_cmd((0x40+9)	, 0) == 0) && rcvr_datablock(csd, 16)) {	/* Read CSD */
					if (CardType & 2) {			/* SDC ver 1.XX */
						*(DWORD*)buff = (((csd[10] & 63) << 1) + ((WORD)(csd[11] & 128) >> 7) + 1) << ((csd[13] >> 6) - 1);
					} else {					/* MMC */
						*(DWORD*)buff = ((WORD)((csd[10] & 124) >> 2) + 1) * (((csd[11] & 3) << 3) + ((csd[11] & 224) >> 5) + 1);
					}
					res = RES_OK;
				}
			}
			break;

		case 10 :		/* Get card type flags (1 byte) */
			*ptr = CardType;
			res = RES_OK;
			break;

		case 11 :		/* Receive CSD as a data block (16 bytes) */
			if (send_cmd((0x40+9)	, 0) == 0		/* READ_CSD */
				&& rcvr_datablock(ptr, 16))
				res = RES_OK;
			break;

		case 12 :		/* Receive CID as a data block (16 bytes) */
			if (send_cmd((0x40+10)	, 0) == 0		/* READ_CID */
				&& rcvr_datablock(ptr, 16))
				res = RES_OK;
			break;

		case 13 :		/* Receive OCR as an R3 resp (4 bytes) */
			if (send_cmd((0x40+58)	, 0) == 0) {	/* READ_OCR */
				for (n = 4; n; n--) *ptr++ = rcvr_spi();
				res = RES_OK;
			}
			break;

		case 14 :	/* Receive SD statsu as a data block (64 bytes) */
			if (send_cmd((0xC0+13)	, 0) == 0) {	/* SD_STATUS */
				rcvr_spi();
				if (rcvr_datablock(ptr, 64))
					res = RES_OK;
			}
			break;

		default:
			res = RES_PARERR;
		}

		release_spi();
	}

	return res;
}


/*-----------------------------------------------------------------------*/
/* Device Timer Interrupt Procedure  (Platform dependent)                */
/*-----------------------------------------------------------------------*/
/* This function must be called in period of 10ms                        */

void disk_timerproc (void)
{
	static BYTE pv;
	BYTE n, s;


	n = Timer1;						/* 100Hz decrement timer */
	if (n) Timer1 = --n;
	n = Timer2;
	if (n) Timer2 = --n;
        
        
	n = pv;
	pv = PINB			 & (0			 | 0			);	// Sample socket switch

	if (n == pv) {					// Have contacts stabled?
		s = Stat;

		if (pv & 0			)			// WP is H (write protected)
			s |= 0x04	;
		else						// WP is L (write enabled) 
			s &= ~0x04	;

		if (pv & 0			)			// INS = H (Socket empty) 
			{
			s |= (0x02	 | 0x01	);
		        }
		else						//INS = L (Card inserted) 
			s &= ~0x02	;

		Stat = s;
	}

}