// Affiche la temperature du capteur interne au MSP430.
// le bouton P1.0 permet d'alterner l'affichage en Celsius ou Kelvin
// les LEDS P2.0 à P2.3 s'allument en proportion avec l'augmentation de 
// temperature (1 LED chaque degré d'incrément)
//******************************************************************************
#include "msp430xG46x.h"
#include "intrinsics.h"
#include "LCD.h"
#include "stdio.h"

#define ADC_DELTA     6                // ~ 1 Deg C delta for LED on
#define CELSIUS       0
#define KELVIN        1

unsigned int ADC_start, mode=0;

void main(void)
{ 
  char str[9];   
  int i;
  float Temp, Volt;
  
  WDTCTL = WDTPW + WDTHOLD;                 // Stop watchdog
  
  ADC12CTL0 = SHT0_8 + REF2_5V + REFON + ADC12ON; // Config ADC12
  ADC12CTL1 = SHS_1 + SHP + CONSEQ_2;       // TA trig., 
                                            // Sample/Hold Pulse Mode
                                            // Repetitive conversion of 1 channel
  ADC12MCTL0 = SREF_1 + INCH_10;            // Channel A10, Vref+
  ADC12IE |= 0x001;                         // Enable ADC12IFG.0
  
  // fréquence du timer = 32*32768/CCR0 [Hz]
  TACCR0 = 13600;                           // Delay for reference start-up
  TACTL = TACLR + MC_1 + TASSEL_2;          // up mode, SMCLK
  TACTL = TASSEL_2 + MC_2;                  // SMCLK, cont-mode
  TACCTL1 = OUTMOD_4;                       // Toggle on EQU1 (TAR = 0)

  ADC12CTL0 |= ENC;                         // Enable ADC12

  while (!(ADC12IFG & 0x0001));             // Wait for first conversion?

  ADC_start = ADC12MEM0;                    // Read out 1st ADC value

  P2OUT = 0;                                // Clear P5
  P2DIR |= 0x0F;                            // P2.x as output
  
  P1IE  |= 0x01;                            // enable interrupt P1.0
  P1IFG  = 0;  

  LCD_init();
   __enable_interrupt();
   
  while (1) {
    Volt = ADC12MEM0 * 2.5 / 4095;
    Temp = (Volt - 0.986) / 0.00355;
    if (mode == KELVIN)
    {  Temp = Temp + 273.2;
        sprintf(str,"T=%5.1fK",Temp);
    }
    else
        sprintf(str,"T=%5.1fC",Temp);
    
    LCD_print (str);
    for (i=1;i<30000;i++);
  }
}

//routine d'interruption qui survient lorsque P1.0 a un flanc
#pragma vector=PORT1_VECTOR
__interrupt void Port1_ISR (void) // PORT1ISR (void)
{ 
  if (P1IFG == 0x01)   
    mode ^= 1;

  P1IFG = 0;
}


#pragma vector = ADC12_VECTOR
__interrupt void ADC12_ISR(void)
{ 
  unsigned int i, adc;
  
  adc = ADC12MEM0;
  i = (adc > ADC_start) * (adc - ADC_start) / ADC_DELTA;
  
  if (i < 1) 
    P2OUT = 0x00;
  if (i >= 1)
    P2OUT = 0x01;
  if (i >= 2)
    P2OUT = 0x03;
  if (i >= 3)
    P2OUT = 0x07;
  if (i >= 4)
    P2OUT = 0x0F;
}