Timer32.c

#include "msp.h"
#include "Timer32.h"
#include "Common.h"
#include "CortexM.h"
// Sections borrowed from Jonathan Valvano UTexas
extern uint32_t SystemCoreClock;

// NOTE: By default the MCLK is running at 3MHz
double systemTimer = 0;
void (*Timer32_1_PeriodicTask)(void);   // user function
void (*Timer32_2_PeriodicTask)(void);   // user function

static unsigned long timer1Period;
static unsigned long timer2Period;
///////////////////////////////////////////////////////
//
// Helper function
//
///////////////////////////////////////////////////////
unsigned long  CalcPeriodFromFrequency (double Hz)
{
	double period = 0.0;
	period = (double)SystemCoreClock/Hz;
	period = period;   // we divide by 2 because we want an interrupt for both the rising edge and the falling edge
	return (unsigned long) period;
}

BOOLEAN timeOut = FALSE;
// this will timeout after 1 millisecond
void MS_Timeout_Handler(void)
{
	timeOut = TRUE;
}

// ***************** Timer32_1_Init ****************
// Activate Timer32 Timer 1 interrupts to run user task periodically
// Inputs:  task is a pointer to a user function
//          period in units (1/(bus clock)/div), 32 bits
//          div is clock divider for Timer32 Timer 1
//            T32DIV1   for input clock divider /1
//            T32DIV16  for input clock divider /16
//            T32DIV256 for input clock divider /256
// NOTE: The default clock is 3MHz
// Outputs: none
void Timer32_1_Init(void(*task)(void), unsigned long period, enum timer32divider div)
{
	long sr;
	timer1Period = period;
	// default MCLK is 3MHz
	// but set MCLK to 48 MHz
  sr = StartCritical();
	
	// unsigned long function
  Timer32_1_PeriodicTask = task;      
	
	// timer reload value
	// TIMER32_LOAD1
  	TIMER32_LOAD1 = period;    
	
	// clear Timer32 Timer 1 interrupt
	// TIMER32_INTCLR1
  	TIMER32_INTCLR1 = 1;   

	
  // bits31-8=X...X,   reserved
  // bit7,             timer 0=disable, 1=enable
  // bit6,             0 = Timer is in free-running mode, 1=timer in periodic mode
  // bit5,             interrupt 0=disable, 1=enable
  // bit4=X,           reserved
  // bits3-2=??,       input clock divider according to parameter
  // bit1,             0=16bit counter, 1=32-bit counter
  // bit0,             1=one shot mode, 0=wrapping mode
	
	// TIMER32_CONTROL1, enable, periodic, 32 bit counter
  TIMER32_CONTROL1 |= (BIT7 | BIT6 | BIT1); //0xE2;
	
	// interrupts enabled in the main program after all devices initialized
	// NVIC_IPR6
  NVIC_IPR6 = (NVIC_IPR6&0xFFFF00FF)|0x00004000; // priority 2
	
	// enable interrupt 25 in NVIC, NVIC_ISER0
	// NVIC_ISER0
	NVIC_ISER0 |= BIT(25); // changed from 0x2000000

  EndCritical(sr);
}



void T32_INT1_IRQHandler(void)
{
	// acknowledge Timer32 Timer 1 interrupt
	// TIMER32_INTCLR1
  TIMER32_INTCLR1 |= 1;    
	
	// execute user task
  (*Timer32_1_PeriodicTask)();               
	
	// timer reload value to start the timer again
	// TIMER32_LOAD1
	 TIMER32_LOAD1 = timer1Period;
}

// ***************** Timer32_2_Init ****************
// Activate Timer32 Timer 2 interrupts to run user task periodically
// Inputs:  task is a pointer to a user function
//          period in units (1/(bus clock)/div), 32 bits
//          div is clock divider for Timer32 Timer 1
//            T32DIV1   for input clock divider /1
//            T32DIV16  for input clock divider /16
//            T32DIV256 for input clock divider /256
// NOTE: The default clock is 3MHz
// Outputs: none
void Timer32_2_Init(void(*task)(void), unsigned long period, enum timer32divider div)
{
	long sr;
	timer2Period = period;

	// default MCLK is 3MHz
	// but set MCLK to 48 MHz
  	sr = StartCritical();
	
	// unsigned long function
	// assigns the ISR
  	Timer32_2_PeriodicTask = task;      
	
	// timer reload value
	// TIMER32_LOAD2
  	TIMER32_LOAD2 = period;    
	
	// clear Timer32 Timer 2 interrupt
	// TIMER32_INTCLR2
  	TIMER32_INTCLR2 = 1;  

  
	// bits31-8=X...X,   reserved
	// bit7,             timer 0=disable, 1=enable
	// bit6,             0 = Timer is in free-running mode, 1=timer in periodic mode
	// bit5,             interrupt 0=disable, 1=enable
	// bit4=X,           reserved
	// bits3-2=??,       input clock divider according to parameter
	// bit1,             0=16bit counter, 1=32-bit counter
	// bit0,             1=one shot mode, 0=wrapping mode
		
  	//TIMER32_CONTROL2   
  	TIMER32_CONTROL2 |=  (BIT7 | BIT6 | BIT1); //0xE2;

	// interrupts enabled in the main program after all devices initialized
  	NVIC_IPR6 = (NVIC_IPR6&0xFFFF00FF)|0x00004000; // priority 2
	
	// enable interrupt 26 in NVIC, NVIC_ISER0
	// NVIC_ISER0
  	NVIC_ISER0 |= BIT(26); // changed from 0x4000000;         

  	EndCritical(sr);
}



void T32_INT2_IRQHandler(void)
{
	// acknowledge Timer32 Timer 1 interrupt
	// TIMER32_INTCLR2
  TIMER32_INTCLR2 |= 1;    
	
	// execute user task
  (*Timer32_2_PeriodicTask)();               
	
	// timer reload value
	// TIMER32_LOAD2
	TIMER32_LOAD2 = timer2Period;    

}