2021_2022_deeltoets_2

2021-2022 Deeltoets 2

Opgaven

De opgaven kun je vinden op: https://bitbucket.org/HR_ELEKTRO/ems10/wiki/Toetsen/2021-2022_Deeltoets_2.pdf

Uitwerkingen

Toetsvragen 1 en 2

#include <msp430.h> 
#include <stdint.h>

// 1C
#pragma vector = TIMER1_A1_VECTOR
__interrupt void timer1_ISR(void)
{
    P2OUT ^= 1<<1;
    TA1CTL &= ~TAIFG;
}

int main(void)
{
    WDTCTL = WDTPW | WDTHOLD; // stop watchdog timer
    // 1A
    P2DIR |= 1<<2 | 1<<1;
    P2OUT |= 1<<2 | 1<<1;
    // 1B
    BCSCTL3 = LFXT1S_2;
    // Timer 1 use ACLK, up/down mode en input divider = 1
    TA1CTL =  TASSEL_1 | ID_0 | MC_3 | TAIE;
    // Interrupt every 2 seconds = 12000 * 2 = 24000 clocks TACCR0 = 1/2 * 24000 = 12000
    TA1CCR0 = 12000; // niet -1
    // 1C
    P2SEL |= 1<<2;
    P2SEL2 &= ~(1<<2);
    // Output Mode 2:Toggle/Set
    TA1CCTL1 = OUTMOD_2;
    TA1CCR1 = 3000; // niet -1
    __enable_interrupt();

    // 2
    // DCO = 12 MHz
    DCOCTL = 0;
    BCSCTL1 = CALBC1_12MHZ;
    DCOCTL = CALDCO_12MHZ;
    // We volgen de instructies uit de Family User's Guide paragraaf 15.3.1.
    // 1. Set UCSWRST
    UCA0CTL1 |= UCSWRST;
    // 2. Initialize all USCI registers with UCSWRST = 1 (including UCAxCTL1)
    // Parity disabled, LSB first, 8-bit data, One stop bit, UART mode, Asynchronous mode
    UCA0CTL0 = 0;
    // USCI clock source select = SMCLK
    UCA0CTL1 = UCSSEL_2 | UCSWRST;
    // Baudrate = 9600 zie paragraaf 15.3.13 in Family User's Guide.
    // Oversampling mode enabled
    UCA0BR0 = 78;
    UCA0BR1 = 0;
    UCA0MCTL = UCBRS_0 | UCBRF_2 | UCOS16;
    // 3. Configure ports.
    P1SEL |= BIT2 | BIT1;
    P1SEL2 |= BIT2 | BIT1;
    // 4. Clear UCSWRST via software
    UCA0CTL1 &= ~UCSWRST;

    while (1)
    {
        while ((IFG2 & UCA0RXIFG) == 0); // wacht op ontvangst karakter
        char c = UCA0RXBUF;
        if (c == '0')
        {
            P2OUT &= ~(1<<1);
        }
        else if (c == '1')
        {
            P2OUT |= 1<<1;
        }
    }
}

Toetsvraag 3

De antwoorden op toetsvraag 3 kun je vinden op: https://bitbucket.org/HR_ELEKTRO/ems10/wiki/Toetsen/2021-2022_Deeltoets_2_antwoordblad.pdf