ISR code not working

[vinkar]

Hello Friends,

I have an unusual problem :smileyhappy:

I have designed 3 boards (variants of he same app) using the KL04 chip. Now the code used is this -

#include "derivative.h" /* include peripheral declarations */

//void UART0_IRQHandler(void);

// extern void LPTimer_IRQ(void);

// void LPTimer_IRQ(void);

int main(void)

{

    int count;

    uint16_t countTemp = 0;

   // asm(" CPSIE i");

    MCG_C1 |= 0x02;

    SIM_SOPT1 = 0;      

    SIM_SCGC5 |= (SIM_SCGC5_LPTMR_MASK | SIM_SCGC5_PORTB_MASK);//PORTC_PCR1 |= PORT_PCR_MUX(1);//select RTC_CLKIN function

    PORTB_PCR3 |= 0x00000100;    // alternative pin mux selection //

    GPIOB_PDDR |= 0x00000008;    // pin direction //

    PORTB_PCR4 |= 0x00000100;    // alternative pin mux selection //

    GPIOB_PDDR |= 0x00000010;    // pin direction //   

     NVIC_ICPR = 1 << (28);

     NVIC_ISER = 1 << (28);

     SIM_SCGC5|=SIM_SCGC5_LPTMR_MASK;

     /* Reset LPTMR settings */

     SIM_SOPT1 = 0;   

     SIM_SCGC5 |= (SIM_SCGC5_LPTMR_MASK | SIM_SCGC5_PORTB_MASK);//PORTC_PCR1 |= PORT_PCR_MUX(1);//select RTC_CLKIN function

     LPTMR0_CSR=0;  

     LPTMR0_CSR |= 0x00000040;

     LPTMR0_CMR = 600;

     GPIOB_PTOR |= (1 << 3);

     GPIOB_PTOR |= (1 << 4);  

     GPIOB_PTOR |= (1 << 3);

     GPIOB_PTOR |= (1 << 4);  

      /* Start the timer */ 

     LPTMR0_CSR |= LPTMR_CSR_TEN_MASK;

      /* Wait for counter to reach compare value */

     asm("nop");

      while(1){

          asm("nop");

          asm("nop");

          asm("nop");

          asm("nop");

//         if((LPTMR0_CSR & 0x00000080) == 0x00000080){

//             LPTMR0_CSR &= ~LPTMR_CSR_TEN_MASK;

//             LPTMR0_CSR |= 0x00000080;

//             LPTMR0_CSR |= LPTMR_CSR_TEN_MASK;

//             GPIOB_PTOR |= (1 << 3);

//             GPIOB_PTOR |= (1 << 4);  

//         }

      }      

}

void LPTimer_IRQHandler(void){

     asm("nop");

     asm("nop");

     asm("nop");

     asm("nop");

    if((LPTMR0_CSR & 0x00000080) == 0x00000080){

            LPTMR0_CSR &= ~LPTMR_CSR_TEN_MASK;

            LPTMR0_CSR |= 0x00000080;

            LPTMR0_CSR |= LPTMR_CSR_TEN_MASK;

            GPIOB_PTOR |= (1 << 3);

            GPIOB_PTOR |= (1 << 4);  

        }

}

Ideally the controller should be interrupted and the control should go to the ISR (void LPTimer_IRQHandler(void)). What I see here is that in the 1st and the 2nd version of the board the ISR works well. But in the 3rd it doesnt. So, to test the 3rd board I made a pin toggle which is executed fine making me feel that this is a purely software issue.

I am a bit confused as to how this is being done.

I am stating the part number in all the 3 boards -

1) -  M04R4V

       4EYIDK

2) M04R5V

    4EYIDM

3) M04R5V

    ASAUK

Can anyone help me pls

[xiangjun_rong]

Hi, Vinod,

Regarding your question, I have not the FRDM-KL04 board on hand, but I have FRDM-KL02Z board, I have tested the code on my FRDM-KL02Z board, I found out that the LPTMR0_PSR[PCS]=11 in binary for unknown reason  in default state, in the case, it selects the OSCERCLK as clock source, in the case, you should set the OSC32KSEL in SIM_SOPT1 as 10 in binary, in the setting, the CLK source for LPTMR will be from external RTC_CLKIN as Mr Yasuhiko pointed out, pls refer to section 3.8.3.3 LPTMR prescaler/glitch filter clocking options in RM of KL04. But if you use RTC_CLKIN pin, you have to enable PORTA clock in SIM_SCGC5 and set the PORTB_PCR4 = 0x00000100; and set the SIM_SOPT1 =0x80000;

I have developed the code based on the FRDM-KL02 board, with which I can enter the LPTimer_IRQHandler(void) with 1KHz LPO clock source, you can copy the code directly for KL04.

I attach the code, hope it can help you.

[vinkar]

Hello Xiangjun,

I understand ur point. But then how come it works in the other board but not i the new one.

Will nmi_b pin cause any mischief.

Vinod

[vinkar]

Hello Friends,

Thank you very much indeed for your responses.

I sincerely appreciate it.

SO with my code what I am doing is I am making the clock for the LPTMR come from RTC_CLKIN. And since I dont have such a clock its not working. So its all software.

But then how can it be explained that the LPTMR works for my older boards which also doesnt have the RTC_CLKIN. The code is completely the same.

Vinod.

[xiangjun_rong]

Hi, Vinod,

as you know, multiple clock source can drive the LPTMR, pls check the LPTMR0_PSR[PCS] to determine the clock source the LPTMR uses for your old code, I guess the LPTMR uses LPO, whatever.

Pls refer to the section I copied from UM of KL04.

BR

XiangJun Rong

[yasuhikokoumoto]

Hi vinod,

I guess your board has neither EXTAL0 nor XTAL0 oscillator. In the case, the setting SIM_SOPT1 0 would not select any clock for LPTMR. How about 0x000c0000 (i.e. LPO) as SIM_SOPT1 value? Also you should better make the first LPTMR0_CSR setting not 0 but 0x80 to clear the interrupt.

Best regards,
Yasuhiko Koumoto.