Published

PIC Wave Player

SD Card pic16f690 FAT32 wave player.

IntermediateFull instructions provided57
PIC Wave Player

Things used in this project

Hardware components

Microchip pic16f690
×1
8 MHz Crystal
8 MHz Crystal
×1
Capacitor 22 pF
Capacitor 22 pF
×1
Pushbutton switch 12mm
SparkFun Pushbutton switch 12mm
×3
LED (generic)
LED (generic)
×1
Resistor 1k ohm
Resistor 1k ohm
×1
Capacitor 10 µF
Capacitor 10 µF
×1
Memory Socket, SD Card
Memory Socket, SD Card
×1

Story

Read more

Schematics

FAT32 player

Code

sd player

C/C++
//*          SD FAT32 Player      *
// 
// Compile with MPLAB Hi Tech or MPLABX XC8. 
// This code is free to use, for more info   http://www.moty22.co.uk
// pic16f690       
   
#include <htc.h>

#define _XTAL_FREQ 8000000

#define CSsd RC2		//chip select input
#define Stop RA2	//stop pushbutton
#define Play RB5	//play PB
#define Next RB7		//next track PB //RB7
//#define Pause RA1	//pause PB
#define errorLED RC1
#define sdLED RC4	//SD or SDHC optional LED

//prototypes
void main(void);
unsigned char SPI(unsigned char spidata);
char Command(unsigned char frame1, unsigned long adrs, unsigned char frame2 );
void initSD(void);
void readSD(void);
void fat (void);
void file(unsigned int offset, unsigned char sect);

#if defined(__XC8)
  #pragma config FOSC=HS, CP=OFF, CPD=OFF, WDTE=OFF, BOREN=OFF, MCLRE=OFF
#else defined(COMPILER_MPLAB_PICC)
  __CONFIG(WDTDIS & UNPROTECT & HS & MCLRDIS & UNPROTECT & BORDIS & PWRTDIS);	//LVPDIS & 
#endif

unsigned long loc,BootSector, RootDir, SectorsPerFat, RootDirCluster, DataSector, FileCluster, FileSize;	//
unsigned int BytesPerSector, ReservedSectors, card;	//, RootEntries

unsigned char sdhc=0, SectorsPerCluster, Fats;	//standard sd
	
void main(void)
{
	unsigned char fn=1, sn=0;	//file #, sector# 
	
	//OSCCON = 0B1110001;	//8MHz,
	// PIC I/O init
	ANSEL = 0;
	ANSELH = 0;
	TRISC = 0b1000000;		//  rc5=CPP1.
	TRISA = 0b110;   	// switches
	TRISB = 0b10111111;
	//pullup on
	//RABPU = 0;
	#if defined(__XC8)
       nRABPU = 0;
    #else defined(COMPILER_MPLAB_PICC)
       RABPU = 0;
    #endif
    //WPUA1 = 1;	
	WPUA2 = 1;
	WPUB5 = 1;
	WPUB7 = 1;
	
	//ANS8 = 1;	//analogue chan 8
	//RecLED = 0;
	errorLED = 0;
	sdLED = 0;

		//analogue init
	CCP1CON = 0B1100;	//PWM mode
	PR2 = 63;	//33KHz PWM
	T2CON = 0B100;	//prescale 1, post scale 1, timer2 on
	//timer1
	T0CS=0;			//timer0 Internal clock
	PSA=1;			//Prescaler is assigned to the WDT
	
	//SPI init
	SSPCON = 0B110010;	//low speed osc/64(125kHz),enabled,clock idle=H
	CSsd = 1; 		// disable SD
	
	initSD();
	if(sdhc){card = 1;}else{card=512;}	//SD or SDHC
	fat();
	if(BytesPerSector!=512){errorLED=1;}
	
	while(1){
		if(!Play){
			while(Stop){	
				file(fn*32+20,sn);		//32 bytes per file descriptor at offset of 20
				if(FileCluster){	//cluster reads 0 is end of files entries
					loc=(1 + (DataSector) + (unsigned long)(FileCluster-2) * SectorsPerCluster) * card ;
					readSD();
					//__delay_ms(250);
					while(!Next){}
					if(Stop){++fn;}
					if(fn>15){fn=0;++sn;} 
				}else{fn=1;sn=0;}
			}
		}
	}
}

void file(unsigned int offset, unsigned char sect)	//find files
{
	unsigned int r,i;
	unsigned char fc[4], fs[4]; //
	
	CSsd = 0;
	r = Command(17,(RootDir+sect)*card,0xFF);		//read boot-sector for info from file entry
	if(r != 0)errorLED = 1;			//if command failed
	
	while(SPI(0xFF) != 0xFe);	// wait for first byte
	for(i=0;i<512;i++){
		if(i==offset){fc[2]=SPI(0xFF);} 
		else if(i==offset+1){fc[3]=SPI(0xFF);}
		else if(i==offset+6){fc[0]=SPI(0xFF);}
		else if(i==offset+7){fc[1]=SPI(0xFF);}
		
		else if(i==offset+8){fs[0]=SPI(0xFF);}
		else if(i==offset+9){fs[1]=SPI(0xFF);}
		else if(i==offset+10){fs[2]=SPI(0xFF);}
		else if(i==offset+11){fs[3]=SPI(0xFF);}
		else{SPI(0xFF);}
		
	}
	SPI(0xFF);	//discard of CRC
	SPI(0xFF);
	CSsd = 1;SPI(0xFF);
	FileCluster = fc[0] | ( (unsigned long)fc[1] << 8 ) | ( (unsigned long)fc[2] << 16 ) | ( (unsigned long)fc[3] << 24 );
	FileSize = fs[0] | ( (unsigned long)fs[1] << 8 ) | ( (unsigned long)fs[2] << 16 ) | ( (unsigned long)fs[3] << 24 );
	FileSize = FileSize/512+1;		//file size in sectors
}
	
void readSD(void)
{
	unsigned int i,r;
	unsigned char data;
	
	CSsd = 0;
	r = Command(18,loc,0xFF);	//read multi-sector
	if(r != 0)errorLED = 1;			//if command failed

	while(Stop && Next && FileSize--)
	{	
		while(SPI(0xFF) != 0xFE);	// wait for first byte
		for(i=0;i<512;i++){
			while(!T0IF){}
			TMR0=165;		//(256-91) 91 counts to get 22KHz, play speed
			T0IF = 0;
			data = SPI(0xFF);
			DC1B1 = data & 2;	//shift byte to get the required PWM duty cycle 
			DC1B0 = data & 1;
			CCPR1L = (data >> 2);
		}
		SPI(0xFF);	//discard of CRC
		SPI(0xFF);
	}
	Command(12,0x00,0xFF);	//stop transmit
	SPI(0xFF);
	SPI(0xFF);
	CSsd = 1;SPI(0xFF);
}

void fat (void)
{
	unsigned int r,i;
	unsigned char pfs[4],bps1,bps2,rs1,rs2,spf[4],rdc[4]; //pfs=partition first sector ,de1,de2,spf1,d[7]
	
	CSsd = 0;
	r = Command(17,0,0xFF);		//read MBR-sector
	if(r != 0)errorLED = 1;			//if command failed
	
	while(SPI(0xFF) != 0xFe);	// wait for first byte
	for(i=0;i<512;i++){
		if(i==454){pfs[0]=SPI(0xFF);}	//pfs=partition first sector
		else if(i==455){pfs[1]=SPI(0xFF);}
		else if(i==456){pfs[2]=SPI(0xFF);}
		else if(i==457){pfs[3]=SPI(0xFF);}
		else{SPI(0xFF);}
		
	}
	SPI(0xFF);	//discard of CRC
	SPI(0xFF);
	CSsd = 1;SPI(0xFF);
	//convert 4 bytes to long int
	BootSector = pfs[0] | ( (unsigned long)pfs[1] << 8 ) | ( (unsigned long)pfs[2] << 16 ) | ( (unsigned long)pfs[3] << 24 );
	
	CSsd = 0;
	r = Command(17,BootSector*card,0xFF);		//read boot-sector
	if(r != 0)errorLED = 1;			//if command failed
	
	while(SPI(0xFF) != 0xFe);	// wait for first byte
	for(i=0;i<512;i++){
		
		if(i==11){bps1=SPI(0xFF);} //bytes per sector
		else if(i==12){bps2=SPI(0xFF);}
		else if(i==13){SectorsPerCluster=SPI(0xFF);}
		else if(i==14){rs1=SPI(0xFF);}
		else if(i==15){rs2=SPI(0xFF);}
		else if(i==16){Fats=SPI(0xFF);}	//number of FATs
		else if(i==36){spf[0]=SPI(0xFF);}
		else if(i==37){spf[1]=SPI(0xFF);}
		else if(i==38){spf[2]=SPI(0xFF);}
		else if(i==39){spf[3]=SPI(0xFF);}
		else if(i==44){rdc[0]=SPI(0xFF);}
		else if(i==45){rdc[1]=SPI(0xFF);}
		else if(i==46){rdc[2]=SPI(0xFF);}
		else if(i==47){rdc[3]=SPI(0xFF);}
		else{SPI(0xFF);}
		
	}
	SPI(0xFF);	//discard of CRC
	SPI(0xFF);
	CSsd = 1;SPI(0xFF);		
	
	BytesPerSector = bps1 | ( (unsigned int)bps2 << 8 );
	ReservedSectors = rs1 | ( (unsigned int)rs2 << 8 );	//from partition start to first FAT
	RootDirCluster = rdc[0] | ( (unsigned long)rdc[1] << 8 ) | ( (unsigned long)rdc[2] << 16 ) | ( (unsigned long)rdc[3] << 24 );
	SectorsPerFat = spf[0] | ( (unsigned long)spf[1] << 8 ) | ( (unsigned long)spf[2] << 16 ) | ( (unsigned long)spf[3] << 24 );
	DataSector = BootSector + (unsigned long)Fats * (unsigned long)SectorsPerFat + (unsigned long)ReservedSectors;	// + 1  
	RootDir = (RootDirCluster -2) * (unsigned long)SectorsPerCluster + DataSector;
}

unsigned char SPI(unsigned char spidata)		// send character over SPI
{
	SSPBUF = spidata;			// load character
	while (!BF);		// sent
	return SSPBUF;		// received character
}

char Command(unsigned char frame1, unsigned long adrs, unsigned char frame2 )
{	
	unsigned char i, res;
	
	//SPI(0xFF);
	SPI((frame1 | 0x40) & 0x7F);	//first 2 bits are 01
	SPI((adrs & 0xFF000000) >> 24);		//first of the 4 bytes address
	SPI((adrs & 0x00FF0000) >> 16);
	SPI((adrs & 0x0000FF00) >> 8);
	SPI(adrs & 0x000000FF);	
	SPI(frame2 | 1);				//CRC and last bit 1

	for(i=0;i<10;i++)	// wait for received character
	{
		res = SPI(0xFF);
		if(res != 0xFF)break;
	}
	return res;	  
}

void initSD(void)
{
	unsigned char i,r[4];
	
	CSsd=1;
	for(i=0; i < 10; i++)SPI(0xFF);		// min 74 clocks
	CSsd=0;			// Enabled for SPI mode

	//if (Command(0x00,0,0x95) !=1) errorLED = 1;	//start SPI mode
	i=100;	//try enter idle state for up to 100 times
	while(Command(0x00,0,0x95) !=1 && i!=0)
	{ 
		CSsd=1;
		SPI(0xFF);
		CSsd=0;
		i--;
	}
	if(i==0)	errorLED = 1;	//idle failed
		
	if (Command(8,0x01AA,0x87)==1){					//check card is 3.3V
		r[0]=SPI(0xFF); r[1]=SPI(0xFF); r[2]=SPI(0xFF); r[3]=SPI(0xFF);		//rest of R7
		if ( r[2] == 0x01 && r[3] == 0xAA ){ 		//Vdd OK (3.3V)
			
			//Command(59,0,0xFF);		//CRC off
			Command(55,0,0xFF);
			while(Command(41,0x40000000,0xFF)){Command(55,0,0xFF);} 	//ACMD41 with HCSsd bit
			}
	}else{errorLED = 1;} 
	
	if (Command(58,0,0xFF)==0){		//read CCSsd in the OCR - SD or SDHC
		r[0]=SPI(0xFF); r[1]=SPI(0xFF); r[2]=SPI(0xFF); r[3]=SPI(0xFF);		//rest of R3
		sdhc=r[0] & 0x40;
		if(r[0] & 0x40)sdLED=1;  
	}
	
	SSPM1 = 0;	// full speed 2MHz
	CSsd = 1;SPI(0xFF);
	
}

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