FTM Timer Confusion

[Jana_muralidharan]

So, I am trying to start the timer FTM0/FTM1 it, upon running of the timer code it stucks at the HardFault why but the same code with FTM2 works perfectly fine why?? 

the not working code

#include "MKE02Z4.h"

/* ================= GLOBALS ================= */
volatile uint8_t uartFlag = 0;

/* ================= PROTOTYPES ================= */
void init_clock(void);
void init_uart0(void);
void init_FTM1(void);
void UART_Send(const char *s);

/* ================= FTM1 ISR ================= */
void FTM1_IRQHandler(void)
{
    /* Clear overflow flag (write 0 while set) */
    FTM1->SC &= ~FTM_SC_TOF_MASK;

    uartFlag = 1;
}

/* ================= MAIN ================= */
int main(void)
{
    init_clock();
    init_uart0();
    init_FTM1();

    UART_Send("FTM1 Initialized\r\n");

    while (1)
    {
        if (uartFlag)
        {
            uartFlag = 0;
            UART_Send("A\r\n");
        }

        __WFI();   /* wait for interrupt */
    }
}

/* ================= CLOCK INIT ================= */
void init_clock(void)
{
    /*
     * Assume internal clock already configured by SDK startup
     * Bus clock = 32 MHz
     */
    SIM->BUSDIV = 0x01;   /* divide by 1 */
}

/* ================= UART0 INIT ================= */
void init_uart0(void)
{
    /* Enable UART0 clock */
    SIM->SCGC |= SIM_SCGC_UART0_MASK;

    /* UART0 pin select (TX/RX) */
    SIM->PINSEL |= SIM_PINSEL_UART0PS_MASK;

    /* Disable TX inversion (important!) */
    SIM->SOPT &= ~SIM_SOPT_TXDME_MASK;

    /*
     * 9600 baud @ 32 MHz
     * SBR = 32e6 / (16 * 9600) ≈ 208
     */
    UART0->BDH = 0x00;
    UART0->BDL = 53;

    UART0->C1 = 0x00;
    UART0->C2 = UART_C2_TE_MASK | UART_C2_RE_MASK;
}

/* ================= FTM1 INIT ================= */
void init_FTM1(void)
{
    /* Enable FTM1 clock */
    SIM->SCGC |= SIM_SCGC_FTM1_MASK;
    __DSB();

    /* ---- VERY IMPORTANT ORDER (KE02 SAFE) ---- */

    /* Stop counter completely */
    FTM1->SC = 0;

    /* Disable write protection (WRITE ONCE) */
    FTM1->MODE = FTM_MODE_WPDIS_MASK;

    /* Reset counter */
    FTM1->CNTIN = 0;
    FTM1->CNT   = 0;

    /*
     * 32 MHz / 128 = 250 kHz
     * 250000 ticks = 1 second
     */
    FTM1->MOD = 249999;

    /* Enable overflow interrupt, prescaler = 128 */
    FTM1->SC = FTM_SC_PS(7) | FTM_SC_TOIE_MASK;

    /* Enable NVIC */
    NVIC_EnableIRQ(FTM1_IRQn);

    /* START TIMER (LAST STEP ONLY) */
    FTM1->SC |= FTM_SC_CLKS(1);
}

/* ================= UART SEND ================= */
void UART_Send(const char *s)
{
    while (*s)
    {
        while (!(UART0->S1 & UART_S1_TDRE_MASK));
        UART0->D = *s++;
    }
}

 the working code

#include "MKE02Z4.h"

/* ================= GLOBALS ================= */
volatile uint8_t uartFlag = 0;

/* ================= PROTOTYPES ================= */
void init_clock(void);
void init_uart0(void);
void init_FTM2(void);
void UART_Send(const char *s);

/* ================= FTM2 ISR ================= */
void FTM2_IRQHandler(void)
{
    /* Clear overflow flag (write 0 while set) */
    FTM2->SC &= ~FTM_SC_TOF_MASK;

    uartFlag = 1;
}

/* ================= MAIN ================= */
int main(void)
{
    init_clock();
    init_uart0();
    init_FTM2();

    UART_Send("FTM2 Initialized\r\n");

    while (1)
    {
        if (uartFlag)
        {
            uartFlag = 0;
            UART_Send("A\r\n");
        }

        __WFI();   /* wait for interrupt */
    }
}

/* ================= CLOCK INIT ================= */
void init_clock(void)
{
    /*
     * Assume internal clock already configured by SDK startup
     * Bus clock = 32 MHz
     */
    SIM->BUSDIV = 0x01;   /* divide by 1 */
}

/* ================= UART0 INIT ================= */
void init_uart0(void)
{
    /* Enable UART0 clock */
    SIM->SCGC |= SIM_SCGC_UART0_MASK;

    /* UART0 pin select (TX/RX) */
    SIM->PINSEL |= SIM_PINSEL_UART0PS_MASK;

    /* Disable TX inversion (important!) */
    SIM->SOPT &= ~SIM_SOPT_TXDME_MASK;

    /*
     * 9600 baud @ 32 MHz
     * SBR = 32e6 / (16 * 9600) ≈ 208
     */
    UART0->BDH = 0x00;
    UART0->BDL = 53;

    UART0->C1 = 0x00;
    UART0->C2 = UART_C2_TE_MASK | UART_C2_RE_MASK;
}

/* ================= FTM2 INIT ================= */
void init_FTM2(void)
{
    /* Enable FTM2 clock */
    SIM->SCGC |= SIM_SCGC_FTM2_MASK;
    __DSB();

    /* ---- VERY IMPORTANT ORDER (KE02 SAFE) ---- */

    /* Stop counter completely */
    FTM2->SC = 0;

    /* Disable write protection (WRITE ONCE) */
    FTM2->MODE = FTM_MODE_WPDIS_MASK;

    /* Reset counter */
    FTM2->CNTIN = 0;
    FTM2->CNT   = 0;

    /*
     * 32 MHz / 128 = 250 kHz
     * 250000 ticks = 1 second
     */
    FTM2->MOD = 249999;

    /* Enable overflow interrupt, prescaler = 128 */
    FTM2->SC = FTM_SC_PS(7) | FTM_SC_TOIE_MASK;

    /* Enable NVIC */
    NVIC_EnableIRQ(FTM2_IRQn);

    /* START TIMER (LAST STEP ONLY) */
    FTM2->SC |= FTM_SC_CLKS(1);
}

/* ================= UART SEND ================= */
void UART_Send(const char *s)
{
    while (*s)
    {
        while (!(UART0->S1 & UART_S1_TDRE_MASK));
        UART0->D = *s++;
    }
}

[Alice_Yang]

Hi @Jana_muralidharan 

Please debug to check whether the FTM1 clock is enabled and verify if the counter register is functioning properly.

BR

Alice 

[Jana_muralidharan · Accepted solution]

I actually found the error

It is that I used registers that are specific to only FTM2,

So, after removing the unwanted registers it worked perfectly fine.

And I found out that HardFault Error will only occur when, We use register which are not there in the first place.

Hey and thanks for your attention to this query thanks.....