Working example for disabling and using the SWD and nRST pins on the MSPM0C1104, without bricking the chip

MSPM0C110x_Special_Pin_Example.c

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#include "ti_msp_dl_config.h"

void setupSWDPinsAsGPIO(void)
{
    DL_GPIO_initDigitalOutput(IOMUX_PINCM20);
    DL_GPIO_initDigitalOutput(IOMUX_PINCM21);

    DL_GPIO_clearPins(GPIOA, DL_GPIO_PIN_19 | DL_GPIO_PIN_20);

    DL_GPIO_enableOutput(GPIOA, DL_GPIO_PIN_19 | DL_GPIO_PIN_20);
}
void setupNRSTPinAsGPIO(void)
{
    DL_GPIO_initDigitalOutput(IOMUX_PINCM2);

    DL_GPIO_clearPins(GPIOA, DL_GPIO_PIN_1);

    DL_GPIO_enableOutput(GPIOA, DL_GPIO_PIN_1);
}

int main(void)
{
    SYSCFG_DL_init();

    /* LED on by default */
    uint16_t counter = 0;
    uint8_t swdEnabled = 1;
    while (1) {
        if (!DL_GPIO_readPins(
                GPIO_SWITCHES_PORT, GPIO_SWITCHES_USER_SWITCH_1_PIN)) {
            delay_cycles(2500000);
            DL_GPIO_setPins(GPIOA, DL_GPIO_PIN_20);
            DL_GPIO_clearPins(GPIOA, DL_GPIO_PIN_19);
            DL_GPIO_clearPins(GPIOA, DL_GPIO_PIN_1);
            delay_cycles(2500000);
            DL_GPIO_setPins(GPIO_SWITCHES_PORT, GPIO_LEDS_USER_LED_1_PIN);
            DL_GPIO_clearPins(GPIOA, DL_GPIO_PIN_20);
            DL_GPIO_setPins(GPIOA, DL_GPIO_PIN_19);
            DL_GPIO_setPins(GPIOA, DL_GPIO_PIN_1);
            delay_cycles(2500000);
            DL_GPIO_setPins(GPIOA, DL_GPIO_PIN_20);
            DL_GPIO_clearPins(GPIOA, DL_GPIO_PIN_19);
            DL_GPIO_clearPins(GPIOA, DL_GPIO_PIN_1);
            delay_cycles(2500000);
            DL_GPIO_clearPins(GPIO_SWITCHES_PORT, GPIO_LEDS_USER_LED_1_PIN);
            DL_GPIO_clearPins(GPIOA, DL_GPIO_PIN_20);
            DL_GPIO_setPins(GPIOA, DL_GPIO_PIN_19);
            DL_GPIO_setPins(GPIOA, DL_GPIO_PIN_1);
            if (counter < 0xFFFF) {
                counter++;
            }
            if (counter == 100) {
                DL_SYSCTL_disableSWD();
                DL_SYSCTL_disableNRSTPin();
                setupSWDPinsAsGPIO();
                setupNRSTPinAsGPIO();
                swdEnabled = 0;
            }
        } else {
            if (swdEnabled == 0) {
                // Enable SWD - Doesn't seem to actually work
                SYSCTL->SOCLOCK.SWDCFG = SYSCTL_SWDCFG_KEY_VALUE;
                swdEnabled = 1;
                // And so we reboot
                DL_SYSCTL_resetDevice(DL_SYSCTL_RESET_POR);
            }
            delay_cycles(1000000);
            DL_GPIO_setPins(GPIO_SWITCHES_PORT, GPIO_LEDS_USER_LED_1_PIN);
            delay_cycles(1000000);
            DL_GPIO_clearPins(GPIO_SWITCHES_PORT, GPIO_LEDS_USER_LED_1_PIN);
        }
    }
}