//DATA1
//Program to do simple data logging
//Written for PIC12F683 to be compiled with the CC5X compiler
//Clock frequency left at 4MHz default

//PREPROCESSOR section =====================================================

#include "12F683.H"				//PIC device file
#include "delay_ms.h"

#pragma config = 0b.11.1100.0100//Core device configuration
								//11. Brown-out Detect disabled
								//11 Code Protects off
								//0 MCLR/GP3 set to digital input
								//0. Powerup timer enabled
								//0 Watchdog timer disabled
								//100 Oscillator set to INTRCIO
								
//VARIABLES section ========================================================

#define ESC 	GPIO.1			//GP1 (Pin7) is ESC
#define LED 	GPIO.5			//GP5 (Pin2) is LED

uns16 ADC_VALUE;				//ADC value
uns16 LEVEL1;					//1st warning threshold
char p;							//p used in varous counters


//FUNCTIONS section ========================================================

void write_data()				//Function to write to EEPROM memory
{
	GIE = 0;					//Disable all interrupts
	EECON1.2 = 1;				//WREN: enable writing to memory
    PIR1.7 = 0;					//EEIF: Clear this bit which gets set after each write
	
	EECON2 = 0x55;				//Required before writing to memory
	EECON2 = 0xAA;				//Required before writing to memory
	EECON1.1 = 1;				//WR: Writes data EEDAT to address EEADR
	while(EECON1.1==1);			//Wait for write to complete (becomes 0 when complete)

	EEADR++;					//Increment the address by 1 for next write (8 bit 0-255)
								//Overflows to 0 so data will keep over-writing when addresses are used up
	
	EECON1.2 = 0;				//WREN: disable write cycles
    //GIE = 1;					//Enable interrupts if being used
}

//-----------------------------------------------------------------------------

void adc_value()				//Function to run ADC conversion
{
	//ADCON0 structure...		//1  Right justify
    							//0  Vdd reference
    							//00 Not used
	   							//10 Input channel (CHS0) is AN2 (THIS PART CHANGES BELOW)
    							//0  ADC capture (GO) not started
    							//1  ADC enabled

	ADCON0 = 0b.1000.1101;		//Makes AN3 channel active
    	
    //Run ADC
    	for(p=0; p<1; p++);		//Delay for acquisition capacitor to charge (1=15uS, 10=90uS)
		ADIF = 0;				//Clear the ADC Complete flag
		ADCON0.1 = 1;			//GO: Start ADC acquisition
		while(ADIF==0);			//Wait for conversion to complete (becomes 0 when complete)

	//Determine complete ADC value				
		ADC_VALUE = ADRESH;				//Copies ADRESH value from an 8bit register to 16bit variable
		ADC_VALUE = ADC_VALUE<<8;		//Moves all bits 8 places left
		ADC_VALUE = ADC_VALUE|ADRESL;	//| merges lower 8 bits with upper 2

	//Write both ADC values to memory
//		EEDAT = ADRESH;					//Copy high portion of ADC value to EEPROM data register
//		write_data();					//Write to memory
		
		EEDAT = ADRESL;					//Copy high portion of ADC value to EEPROM data register
		write_data();					//Write to memory
	
	ESC=1;								//Signal to measure time to write to EEPROM
    for(p=0; p<1; p++);
	ESC=0;

}
    	
//===========================================================================

void main()						//main program
{
//Main port settings (all ports are listed for convenience; some are commented out)
//	TRISIO0 = 0;				//Sets GP0/AN0 (pin7) to Output
    TRISIO1 = 0;				//Sets GP1/AN1 (pin6) to Output (ESC)
//  TRISIO2 = 1;				//sets GP2/AN2 (pin5) to Input (PACK1)
//  TRISIO3 = 1;				//sets GP3 (pin4) to Input
    TRISIO4 = 1;				//sets GP4/AN3 (pin3) to Input (PACK2)
    TRISIO5 = 0;				//Sets GP5 (pin2) to Output (LED)
    
//	ANS0 = 0;					//Sets AN0 (pin7) to digital
    ANS1 = 0;					//Sets AN1 (pin6) to digital
//  ANS2 = 1;					//Sets AN2 (pin5) to analogue (PACK1)
    ANS3 = 1;					//Sets AN3 (pin3) to analogue (PACK2)
    
    CMCON0 = 0b.111;			//Switches all 3 comparator ports off
	
//Static ADC settings
    ANSEL.4 = 1;				//ADCS: Set AD Conversion Clock to Fosc/16
    ANSEL.5 = 0;				//part of above
    ANSEL.6 = 1;				//part of above
    ADIE = 0;					//ADC interrupts disabled
    
//Static EEPROM data logging settings
    EECON1.3 = 0;				//WRERR: clear on startup in case previously set
    EEADR = 0;					//Set address to be used for first write
    
//-----------------------------------------------------------------------------

	ESC=0;
	
//Flash LED three times on startup	
	for (p=0; p<5; p++)
	{
		LED=1;
		delay_ms(500);
		LED=0;
		delay_ms(500);
	}

//Set warning thresholds to suit resistor divider and pack voltages
	LEVEL1=500;							//ADC trigger level
	
    while(1)							//Run the following in an infinite loop
    { 
		adc_value();					//Find ADC value
		
		if (ADC_VALUE<=LEVEL1)			//If battery reaches threshold
		{
			while (ADC_VALUE>1) LED=1;	//Keep LED on
		}

					
	}							//end while

}								//end main