FTM Timer Confusion

Jana_muralidharan — Fri, 26 Dec 2025 11:29:37 GMT

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++; } }

Re: FTM Timer Confusion

Alice_Yang — Mon, 29 Dec 2025 03:55:55 GMT

Hi @Jana_muralidharan

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

Alice

Re: FTM Timer Confusion

Jana_muralidharan — Mon, 29 Dec 2025 05:19:34 GMT

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.....

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