Setup Timers

#include <timer.h>

	//----- SETUP TIMER 4/5 -----
	//Used for: Heartbeat
	OpenTimer45(T4_ON & T4_GATE_OFF & T4_PS_1_1 & T4_SOURCE_INT, (INSTRUCTION_CLOCK_FREQUENCY / 1000));		//1mS irq, 1:1 prescaller
	WriteTimer45(0);
	ConfigIntTimer45(T4_INT_PRIOR_1 & T4_INT_ON);			//Interrupt priority level 1

	//----- SETUP TIMER 6 -----
	//Used for: Buzzer PWM
	//4000Hz = 250uS per complete PWM cycle
	T6CON = 0x8000;				//Timer on, 16bit, 1:1 (Fosc /2)
	PR6 = (INSTRUCTION_CLOCK_FREQUENCY / 8000);
	TMR6 = 0;

	_T6IP = 4;		 		//7(highest) to 1(lowest)
	_T6IF = 0;
	_T6IE = 0;

	//----- SETUP TIMER 7 -----
	//Used for: 
	//Trigger every 60uS
	T7CON = 0x8000;				//Timer on, 16bit, 1:1 (Fosc /2)
	PR7 = (60 * 40);			//40 cycles per 1uS
	TMR7 = 0;

	_T7IP = 3;		 		//7(highest) to 1(lowest)
	_T7IF = 0;
	_T7IE = 1;

Alternatively setup 32bit timer without the library

	//----- SETUP TIMER 4/5 -----
	//Used for: Heartbeat
	T5CONbits.TON = 0;			//Stop any 16-bit Timer3 operation
	T4CONbits.TON = 0;			//Stop any 16/32-bit Timer3 operation
	T4CONbits.T32 = 1;			//Enable 32-bit Timer mode
	T4CONbits.TCS = 0;			//Select internal instruction cycle clock
	T4CONbits.TGATE = 0;		//Disable Gated Timer mode
	T4CONbits.TCKPS = 0b00;		//Select 1:1 Prescaler
	TMR5 = 0x00;				//Clear 32-bit Timer (msw)
	TMR4 = 0x00;				//Clear 32-bit Timer (lsw)
	PR5 = (INSTRUCTION_CLOCK_FREQUENCY / 1000) >> 16;		//Load 32-bit period value (msw)
	PR4 = (INSTRUCTION_CLOCK_FREQUENCY / 1000) & 0xffff;	//Load 32-bit period value (lsw)
	_T5IP = 0x01;				//Set Timer Interrupt Priority Level - 7(highest) to 1(lowest)
	_T5IF = 0;					//Clear Timer Interrupt Flag
	_T5IE = 1;					//Enable Timer interrupt
	T4CONbits.TON = 1;			//Start 32-bit Timer

Timer Interrupt Functions

//Timer 45 Interrupt
void __attribute__((interrupt, auto_psv)) _T5Interrupt(void)
{
	_T5IF = 0;									 //Clear interrupt flag

//Timer 6 interrupt
void __attribute__((interrupt, auto_psv)) _T6Interrupt(void)
{
	_T6IF = 0;									 //Clear interrupt flag

//Timer 7 interrupt
void __attribute__((interrupt, auto_psv)) _T7Interrupt(void)
{
	_T7IF = 0;									 //Clear interrupt flag