ADC10 en el MSP430

El ADC10 se pone en modo automático continuo. El valor de ADC10MEM se lee cada 500 ms. con el temporizador.

main.c

#include <msp430.h>
#include <ti/mcu/msp430/Grace.h>

/*
 *  ======== main ========
 */
int main(void)
{
    Grace_init();                   // Activate Grace-generated configuration
    ADC10CTL0 |= ADC10SC;    // comenzar conversion
    __bis_SR_register(LPM3 + GIE);
}

InterruptVectors_init.c

/*
 *  ======== Timer1_A3 Interrupt Service Routine ======== 
 */
#pragma vector=TIMER1_A0_VECTOR
__interrupt void TIMER1_A0_ISR_HOOK(void)
{
    /* USER CODE START (section: TIMER1_A0_ISR_HOOK) */
    P1OUT ^= BIT0;
 if (ADC10MEM < 512) {
  P2OUT |= BIT0;
  P2OUT &= ~BIT1;
 } else {
  P2OUT &= ~BIT0;
  P2OUT |= BIT1;
 }
    /* USER CODE END (section: TIMER1_A0_ISR_HOOK) */
}

ADC10_init.c

/*
 *  ======== ADC10_graceInit ========
 *  Initialize MSP430 10-bit Analog to Digital Converter
 */
void ADC10_graceInit(void)
{
    /* USER CODE START (section: ADC10_graceInit_prologue) */
    /* User initialization code */
    /* USER CODE END (section: ADC10_graceInit_prologue) */

    /* disable ADC10 during initialization */
    ADC10CTL0 &= ~ENC;

    /* 
     * Control Register 0
     * 
     * ~ADC10SC -- No conversion
     * ~ENC -- Disable ADC
     * ~ADC10IFG -- Clear ADC interrupt flag
     * ~ADC10IE -- Disable ADC interrupt
     * ADC10ON -- Switch On ADC10
     * REFON -- Enable ADC reference generator
     * ~REF2_5V -- Set reference voltage generator = 1.5V
     * MSC -- Enable multiple sample and conversion
     * ~REFBURST -- Reference buffer on continuously
     * ~REFOUT -- Reference output off
     * ~ADC10SR -- Reference buffer supports up to ~200 ksps
     * ADC10SHT_0 -- 4 x ADC10CLKs
     * SREF_1 -- VR+ = VREF+ and VR- = VSS
     * 
     * Note: ~<BIT> indicates that <BIT> has value zero
     */
    ADC10CTL0 = ADC10ON + REFON + MSC + ADC10SHT_0 + SREF_1;

    /* 
     * Control Register 1
     * 
     * ~ADC10BUSY -- No operation is active
     * CONSEQ_2 -- Repeat single channel
     * ADC10SSEL_0 -- ADC10OSC
     * ADC10DIV_0 -- Divide by 1
     * ~ISSH -- Input signal not inverted
     * ~ADC10DF -- ADC10 Data Format as binary
     * SHS_0 -- ADC10SC
     * INCH_1 -- ADC Channel 1
     * 
     * Note: ~<BIT> indicates that <BIT> has value zero
     */
    ADC10CTL1 = CONSEQ_2 + ADC10SSEL_0 + ADC10DIV_0 + SHS_0 + INCH_1;

    /* Analog (Input) Enable Control Register 0 */
    ADC10AE0 = 0x2;

    /* Software delay for REFON to settle */
    __delay_cycles(30000);

    /* enable ADC10 */
    ADC10CTL0 |= ENC;

    /* USER CODE START (section: ADC10_graceInit_epilogue) */
    /* User code */
    /* USER CODE END (section: ADC10_graceInit_epilogue) */
}

main.cfg

Esquema

Aplificar un LM35 con un LM358 y un potenciómetro

Sobre potenciómetros

Conectando la patita izquierda a GND y la derecha a VCC se consigue que la del centra vaya al girar de 0 a VCC (Fig. 1)

El potenciómetro funciona como dos resistencias en serie.  Al girar en el sentido horario se incrementa la primera y se disminuye la segunda. El el sentido anti-horario es a la inversa. (Fig. 2)