#include "config.h"#include "serial.c"#include "serio.c"#include "i2cmsu.c"#include "i2c_memutil.c"// Audio lab// want to sample at roughly 8 Khz rate, or 125 usvolatile unsigned char bufptr, interrupt_flag;volatile unsigned char buf_flag;volatile unsigned char record_mode, playback_mode;volatile unsigned char buf_1[64], buf_2[64];#if defined(HI_TECH_C)void interrupt timer_isr(void)#endif#if defined(__18CXX)#pragma interrupt timer_isrvoid timer_isr(void)#endif{  if (TMR2IF) {    //clear timer interrupt flag	TMR2IF=0;         if (record_mode) {      //read A/D register, save in buffer       if (!buf_flag) buf_2[bufptr] = ADRESH;      else buf_1[bufptr] = ADRESH;      GODONE = 1; // start new conversion      bufptr++;      if (bufptr == 64) {	    bufptr = 0;	    interrupt_flag = 1;        // toggler buffer flag	    buf_flag = ~buf_flag;       }    }    if (playback_mode) {      interrupt_flag = 1;    }  }}#define EEPROM 0xA0     // I2C EEPROM, write lower blk#define EEPROMR 0xA1    // I2C EEPROM, read lower blk#define EEPROMW_HB 0xA8 // I2C EEPROM, write upper blk#define EEPROMR_HB 0xA9 // I2C EEPROM, read upper blk#define DAC 0x58        // I2C DAC 01011000 unsigned int addr;char i, inchar, adc_value;void do_playback(void) {  // playback approach -- start read of ADC at location zero.  playback_mode = 1;  RB4 = 1;  // set switch for playback  pcrlf (); printf("Doing Playback"); pcrlf ();    // this is important, there are TWO internal address counters    // both have to be initialized to zero     // clear lower block address counter  i2c_start();  i2c_put(EEPROM);  // send write cmd to set low block address counter  i2c_put(0); // send high address byte  i2c_put(0); // send low address byte  i2c_stop(); // send stop  // clear upper block address counter  i2c_start();  i2c_put(EEPROMW_HB); //block select = 1  i2c_put(0); // send high address byte  i2c_put(0); // send low address byte  i2c_stop(); // send stop  addr = 0;  // initialize DAC to output zero  i2c_start(); i2c_put(DAC); i2c_put(0x00); i2c_put(0x00); i2c_stop();    // enable interrupts   IPEN = 0; TMR2IF = 0; TMR2IE = 1; PEIE = 1;   GIE = 1;    // start timer 2   TMR2ON = 1 ;  interrupt_flag = 0;  //clear semaphore  do {    i2c_start();    // read byte    if (addr & 0x8000) i2c_put(EEPROMR_HB);    else i2c_put(EEPROMR);      inchar=i2c_get(1);   //NAK    i2c_stop();    // if int flag is set, we not keeping up with sample rate!!!    if (interrupt_flag) putch('!');    // wait for interrupt    while (!interrupt_flag);      interrupt_flag = 0;    i2c_start();   // send to DAC    i2c_put(DAC);    i2c_put(0x00);    i2c_put(inchar);    i2c_stop();    addr = addr+1;    CLRWDT();   //asm("clrwdt")  }while(1);}void do_record(void){  addr = 0; buf_flag = 0;  pcrlf (); printf("Capturing 64K of audio from ADC");   pcrlf ();  record_mode = 1; //   GODONE = 1; // start new converstion  // enable TMR2 interrupt  TMR2IF = 0; TMR2IE = 1;   IPEN = 0; PEIE = 1;  GIE = 1;    TMR2ON = 1; // start timer 2 //  interrupt_flag = 0;  do {    if (interrupt_flag) putch('!');    while (!interrupt_flag) {      CLRWDT();              // asm("clrwdt");     };  // wait for block write    // do block write //    interrupt_flag = 0;    if  (buf_flag) 	      i2c_memwrite(EEPROM,addr,(unsigned char *)buf_2);    else       i2c_memwrite(EEPROM,addr,(unsigned char *)buf_1);    addr = addr + 64;    putch('*');  }while(addr);  // becomes zero on wraparound  printf("64K Capture complete. ");  printf("Press reset to continue.");  pcrlf ();}void main(void){  TRISB4 = 0; // RB4 is output  RB4 = 0;   // initially low for record  // configure A/D   ADCON0 = 0x80;  // sampling freq = Fsoc/32, channel 0   ADCON1 = 0x0E;  ADON = 1;  // Port A analog input, right justification of result   // set baud rate //  serial_init(95,1); // 19200 in HSPLL mode, crystal = 7.3728 MHz   if (!TO || !RI) {    if (!RI) {RI = 1;printf("Software reset has occurred, press reset\n");}    else { // disable watchdog timer, print msg      SWDTEN = 0;printf("Watchdog timer reset has occurred, press reset.\n");    }    pcrlf();    if (i2c_errstat) i2c_print_err();    SLEEP();          //asm("sleep");   }  bufptr=0;buf_flag = 0;  record_mode = 0;  playback_mode = 0;  SWDTEN = 1;  // enable watchdog timer  // enable I2C //  //  i2c_init(17); // about 400Khz  for HSPLL mode, crystal = 7.3728 MHz   i2c_init(12); // lowest value that works, works with slow playback  // configure timer 2  // post scale of 1, prescale of 16, PR2 =76  TOUTPS3 = 0; TOUTPS2 = 0; TOUTPS1 = 0;  TOUTPS0 = 0;  T2CKPS1 = 1; // pre scale of 16 #if defined(HI_TECH_C)   PR2 = 76;    // 6 Khz //#endif#if defined(__18CXX)   PR2 = 114;    // 4 Khz, MCC18 is a somewhat slower //#endif  pcrlf ();printf("Enter 'r'(record), 'p'(playback), 'c'(calibrate), 'e'(examine): ");  inchar=getch();  if (inchar == 'c') {    while(1) {      GODONE = 1;      while (GODONE);  // wait for end of conversion       adc_value = ADRESH;  // upper 8-bits      printf("%x",adc_value);      pcrlf();    }  }  if (inchar == 'e') {    addr = 0;    while(1) {      i2c_memread(EEPROM,addr,(unsigned char *)buf_1); // do read      for(i = 0;i< 64;i++) printf("%x ",buf_1[i]);      pcrlf();      printf("Any key continues read...");pcrlf();      getch();      addr = addr+64;    }  }  if (inchar == 'r') do_record();  if (inchar == 'p') do_playback();  SWDTEN = 0;  // disable watchdog timer  SLEEP();     // asm("sleep")}// end main//for MCC18, place the interrupt vector goto#if defined(__18CXX)#if defined(HIGH_INTERRUPT)#pragma code HighVector=HIGH_INTERRUPT#else#pragma code HighVector=0x0008  #endifvoid HighVector (void){    _asm goto timer_isr _endasm}#pragma code#endif