Backyard Aquaponics
A place to discuss aquaponics

#include <pic.h>


/* Variable declarations */
unsigned char count;
unsigned char seconds;
unsigned char minutes;
unsigned char hours;
unsigned char pump_state;

/* Forward declaration of local functions */
void init(void);
void interrupt timer(void);
void reset_timers(void);

/* Device specific configuration bits */
#define PWRTE     0x08                 /* PoWeR Up Timer (Enable low) - (include to disable) */
#define WDTEN      0x3FFF               /* enable watchdog timer */
#define XT         0x3FFD               /* crystal/resonator */

__CONFIG(WDTEN & XT & ~PWRTE);

/* Local defines */
#define PUMP_ON_TIME   2               /* Time in minutes to have the pump ON */
#define PUMP_OFF_TIME  3               /* Time in minutes to have the pump OFF */
#define PUMP_RELAY     RA0             /* Relay is on PORT A bit 0 */
#define ON             0               /* Output logic 0 turns the pump ON */
#define OFF            1               /* Output logic 1 turns the pump OFF */

/* Main function */
void main(void)
{
   init();                             /* Initialise the device */
   
   while (1)
   {
      CLRWDT();
      if (pump_state == ON)
      {
         if (minutes == PUMP_ON_TIME)
         {
            PUMP_RELAY = OFF;
            pump_state = OFF;
            reset_timers();
         }
      }
      if (pump_state == OFF)
      {
         if (minutes == PUMP_OFF_TIME)
         {
            PUMP_RELAY = ON;
            pump_state = ON;
            reset_timers();
         }
      }     
   };
}

/******************************************************************/
/* Device specific Initialisation                                 */
/*****************************************************************/
void init(void)
{
   /* Intialise the hardware */
   OPTION_REG = 0x84;                  /* Enable Port B Internal pull ups and set TMR0 prescaler ro 32 */
   INTCON = 0xA0;                      /* Enable interrupts for TMR0 */
   T0CS = 0;                           /* Set TMR0 to Timer Mode */
   TRISA = 0;                          /* Set Port A as all outputs */
   TRISB = 0;                          /* Set Port B as all outputs */
   PUMP_RELAY = OFF;                   /* Turn the pump OFF */
   
   /* Initialise the software */
   reset_timers();
   pump_state = OFF;                   /* Pre-set the variable that reflects the pump state */
}

/* Reset time variables to 0 function */
void reset_timers(void)
{
   count = 0;
   seconds = 0;
   minutes = 0;
   hours = 0;
}

/* Timer interupt function */
void interrupt timer(void)
{
   T0IF = 0;                           /* Clear T0 interrupt flag */

   if (++count == 125)                 /* 125 counts of 8mS = 1S */
   {
      count = 0;
      if (++seconds == 60)
      {
         seconds = 0;
         if (++minutes == 60)
         {
            minutes = 0;
            hours++;
         }
      }
   }

}