Fish pump aerator - ready for critique

[nickey 0]

Ok, thanks to all of the great help I've had on this forum, I have this working on my breadboard and would love to hear any comments or criticism that could help me turn it into a better circuit or better coding.

Warn you in advance that my circuit layout and C++ structure is far from professional.

 

//***************************************************************************************
//  Fish tank aerator
//  final version 1.0
//  April 2011
//  Built with Code Composer Studio v4
//***************************************************************************************

#include 

#define freq_10  BIT0		//Port 1 bit 0
#define freq_30  BIT1		//Port 1 bit 1
#define freq_60  BIT2		//Port 1 bit 2
#define dur_5    BIT3		//Port 1 bit 3
#define dur_10   BIT4		//Port 1 bit 4
#define freq_LED BIT5		//Port 1 bit 5 -- LED indicating frequency timer is active
#define dur_LED  BIT6		//Port 1 bit 6 -- LED indicating duration timer (pump) is on
#define pump_relay BIT7		//Port 1 bit 7

void clear_states(void);	//function to reset states
void clear_timers(void);	//function to reset all timers and interrupts and setup Ports
void set_freq_timer(void);	//function to setup frequency timer

 	int freq_state = 0;
 	int dur_state = 0;
 	int timer_state = 0;
   int freq_timer_active = 0;
   int minutes_counter = 0;
   int half_seconds_counter = 0;
   int seconds_counter = 0;		
   int timer_goal = 0;

void main(void)
{
 WDTCTL = WDTPW + WDTHOLD;             // Stop watchdog timer
 clear_timers();						// reset timers 
 clear_states();						// reset states

//***************************************************************
// Poll switches loop
//***************************************************************
 for (;
{
	freq_state = (P1IN & (freq_10 + freq_30 + freq_60));
 	if (freq_state == 00)
	{
		clear_timers();					//if frequency switch is off
		clear_states();					// reset states
	}
	else 
	{
		dur_state = (P1IN & (dur_5 + dur_10));			//get pump duration from switch
		if (timer_state != (freq_state + dur_state))	//if switches have changed since last time
	 	{
	 			clear_timers();							//reset any old timers
				set_freq_timer();						//setup new frequency timer
	 	}
	}
}
}

//***************************************************************
// Clear Timers and Interrupts and Initialize Ports
//***************************************************************
void clear_timers(void) 
{ 
TACCTL0 = 0;						//disable interrrupts for CCR0
freq_timer_active = 0;				//clear active timers
   minutes_counter = 0;				//clear the minutes counter
half_seconds_counter = 0;			//clear the half/seconds counter
seconds_counter = 0;				//reset seconds counter
timer_goal = 0;						//clear timer goal number
P1IE = 0;							//disable all ints port 1
P2IE = 0;							//disable all ints port 2
P1OUT = 0;							//clear all pins on port 1
P1DIR = 0;							//set all port 1 pins to "input"
P1DIR |= dur_LED + freq_LED + pump_relay;	//set port 1 LED and PUMP pins to "output"
}

//***************************************************************	
// Clear States
//***************************************************************
void clear_states(void)
{
freq_state = 0;
 	dur_state = 0;						//reset states
 	timer_state = 0;
freq_timer_active = 0;
}

//***************************************************************
// Setup Frequency Timer
//***************************************************************
void set_freq_timer(void)  
{
timer_state = (freq_state + dur_state);
freq_timer_active = 1;				//indicate frequency timer active
minutes_counter = 0;				//clear the minutes counter
switch (freq_state)
{
 		case freq_10:
   	timer_goal = 10;				//set timer goal to 10 minutes
   	break;
 		case freq_30:
  		timer_goal = 30;				//set timer goal to 30 minutes
   	break;
 		case freq_60:
   	timer_goal = 60;				//set timer goal to 60 minutes
}
P1OUT |= freq_LED;					//set frequency LED on
P1OUT &= ~dur_LED;					//set duration (pump) LED off
P1OUT &= ~pump_relay;				//turn pump off
TACCR0 = 1000;					//0 through 62499 cycles
TACTL = TASSEL_2 + ID_3 + MC_1 + TACLR;  //smclk,divider8,upmode,clrTAR
TACCTL0 = CCIE;						//enable interrupts for CCR0
_BIS_SR(GIE);						//enable interrupts
}

//***************************************************************
//Timer Interrupt Service Routine
//  entered every .007 seconds
//***************************************************************
#pragma vector = TIMERA0_VECTOR
__interrupt void CCR0_ISR (void)
{
if (++half_seconds_counter >= 73)	//if one/half second is up
{
	half_seconds_counter = 0;		//clear the half/seconds counter
	P1OUT ^= freq_LED; 				//toggle the freq led
	if (freq_timer_active == 0)		//if the duration timer is active
	{
		P1OUT ^= dur_LED;			//toggle the duration led
	}
	if (++seconds_counter >= 120)	//if one minute is up
	{
		seconds_counter = 0;		//reset seconds counter
		if (++minutes_counter >= timer_goal) //and if timer is complete
	  	{
	  		minutes_counter = 0;
			if (freq_timer_active == 1)	//and it was the frequency timer
			{
				freq_timer_active = 0;
				P1OUT |= pump_relay; //turn on the pump
				switch (dur_state)
				{
			 			case dur_5:
				   		timer_goal = 5;		//set timer goal to 5 minutes
				   		break;
		  			case dur_10:
		   			timer_goal = 10;	//set timer goal to 10 minutes
			  		}
			}
			else						//must have been duration/pump timer is now complete
			{
				set_freq_timer();		//start frequency timer again
			}
	 	 }
	}
}
}

 

 

water pump circuit.doc

 

water pump code.doc

[Mac 67]

Hi nickey,

 

I think your design looks very nice. If you don't mind another perspective -- I did something similar (below) that uses a jumper to select either a 15 or 30 minute period and a pot to select 0 to 10 minutes of pump on time or always on (green) during each period.

 

Cheerful regards, Mike

[nickey 0]

hi Mike, wow thats just what I was looking for.. My only experience with micro controllers is the TI MSP430 and so I have no knowledge of the PIC systems.. Did it take much programming on your part? Also did that chip allow you to drive a relay directly from one of the pins? My relay has a coil taking about 200ma to activate it so I had to use a transistor.

[Mac 67]

The PIC program is relatively simple. You should be able to something similar on the MSP430.

 

If your relay coil takes 200-ma then you should definitely use a driver transistor.

 

Cheerful regards, Mike

[infrared 3]

Great Job Nickey

Do you have any data on the duty cycle (how much power consumed over time) for your application? It would be great to see a low power fail safe mode to keep the 12 volt system from dropping below a certain level and allowing the starter to be able to start the motor once again for recharging.

[nickey 0]

Thanks for the comments, no I haven't looked at overall power consumption yet.. good idea though. My current thoughts are that since I control the on and off times that I can keep the battery drain to negligible. Might look at your suggestion in the future though.