f_8_21_ledsw1.c

PIC_Hi-Tech_C_Mike_Pearces_I2C_routines Microchi PIC_Hi-Tech C_I2C_for_EEPROM_24LC01B Code

#include "config.h"
#include "delay.h"
#include "serial.c"


// tests power-on reset bits, watchdog timer, and persistent variables 
//prototypes
char getch (void);
void putch (char c);
void pcrlf(void);


/* return 8 bit char from Recieve port */
char getch (void)
{
  unsigned char c;

  while (!RCIF);  /* check RCIF bit */
  c = RCREG;
  return(c);
}

/* send 8 bit char to Recieve port */
void putch (char c)
{
  /* wait until transmit reg empty */
  while (!TXIF); /* check TXIF bit */
  TXREG = c;
}

     
void pcrlf (void)
{
  putch(0x0a);
  putch(0x0d);
}

// 'persisent' prevents reset_cnt from being cleared on reset
// however, reset_cnt is still stored in register bank, so is volatile

// each press and release changes state
#define LED_OFF     0  // turn off
#define LED_ON      1  // turn on
#define LED_BLINK   2  // start blinking
#define LED_STOP    3  // stop blinking

unsigned char state;

void main(void)
{
  serial_init(95,1); // 19200 in HSPLL mode, crystal = 7.3728 MHz 
  pcrlf(); // this subroutine prints a newline to the terminal
  printf("Led Switch/IO started");
  pcrlf();
  state = LED_OFF;
  // RB4 is the output, RB7, RB0 are inputs
  TRISB = 0xEF;
  LATB = 0x00;
  // enable the weak pullup on port B
  RBPU = 0;
  while(1) {
    switch (state) {
      case LED_OFF:
	 printf("LED_OFF");pcrlf();
	  LATB4 = 0;
	  while(RB0);DelayMs(30); // wait for press 
	  while(!RB0);DelayMs(30); // wait for release
	  state = LED_ON;
	  break;
      case LED_ON:
	 printf("LED_ON");pcrlf();
	  LATB4 = 1;
	  while(RB0);DelayMs(30);  // wait for press
	  while(!RB0);DelayMs(30); // wait for release
	  if (RB7) state = LED_BLINK;
	   else state = LED_OFF;
	  break;
      case LED_BLINK:
        printf("LED_BLINK");pcrlf();
	// while not pressed
        while (RB0) { 
	  // toggle LED
	  if (LATB4) LATB4 = 0;
	     else LATB4 = 1;
	  DelayMs(250);
	}
	DelayMs(30);//switch debounce
	state = LED_STOP;
	break;
      case LED_STOP:
        printf("LED_STOP");pcrlf();
	LATB4 = 1;  // freeze on
	while(!RB0); // wait for release
	DelayMs(30);//switch debounce
        state = LED_OFF;
	break;
    }
  }
}