K60 FTM0 overflow interrupt doesn't work

[andreasfrüchtl]

Hi Guys,

this is my first Project with a Freescale K60 uC

I've got a Problem with the Overflow Interrupt on FTM0. I want to jump in the ftm0_isr when the timer reaches the module value, but it doesn't.

Can anybody help me?

I attached the main.c. Thanks in advance

Original Attachment has been moved to: main.c.zip

[DavidS]

Hi Andreas,

I've attached "C" file that has code to initialize the FTM to generate an TOF interrupt.

Look for this snippet in the source file:

//DES 1=test, 0=default code.  Note: FTM defaults to a 16-bit counter...trying to generate TOF interrupt
   {
    unsigned int initialized;
   
    _ftm1_enable_clock();         //enable clock to FTM1 module
    FTM1_MODE = (FTM_MODE_WPDIS_MASK | FTM_MODE_FTMEN_MASK); //Write protection is disabled and all registers are available with no restrictions
    FTM1_CNTIN = FTM_CNTIN_INIT(0);       //Initial Value of the FTM Counter
    FTM1_SC = (FTM_SC_TOF_MASK | FTM_SC_TOIE_MASK | FTM_SC_PS(6));  //FTM counter has overflowed,Enable TOF interrupts,Divide by 6=64 ...default count up mode
    FTM1_MOD = FTM_MOD_MOD(0xdcba);       //Modulo value
    _int_install_isr(INT_FTM1, (void (_CODE_PTR_)(pointer))FTM1_ISR_TEST, NULL);
    initialized = _cortex_int_init(INT_FTM1, 7, TRUE);
    initialized = _cortex_int_enable(INT_FTM1);    //wants IRQ # not Vector #....a pain.

    FTM1_PWMLOAD = 0x200; //DES test
    FTM1_SC |= ( FTM_SC_CLKS(1) ); //System clock(clock selection starts the counting process)

}

Hope this helps.

Regards,

David

[andreasfrüchtl]

Hi David,

Thanks a lot. I forgot to set FTM_SC_TOF_MASK

But I think there is another Problem. The Interrupt Service Routine has to be  set in the Interrupt table.

I have no idea how this is done. I've seen some example Projects, but this looks pretty confusing to me.

i don't want to replace the whole kinetis_sysinit.c

I attached my kinetis_sysinit.c for you

I'll be back in the Laboratory on Wednesday. I hope i can figure it out then.

Have a good Weekend,

best regards,

Andreas

[DavidS]

Hi Andreas,

Good news and thanks for good weekend wises.

you are on the right track for the baremetal coding approach.  You do want to insert the address of the ISR into the vector table.

The Freescale SC code has the vector table as:

#define  VECTOR_078      default_isr     // 0x0000_0138 78    62     FTM0 Single interrupt vector for all sources

#define  VECTOR_079      default_isr     // 0x0000_013C 79    63     FTM1 Single interrupt vector for all sources

#define  VECTOR_080      default_isr     // 0x0000_0140 80    64     FTM2 Single interrupt vector for all sources

The K60 product page has a Download link to the SC code base for CW and IAR:

Hope you have a godd weekend too.

Regards,

David

[andreasfrüchtl]

Hi David,

i took your advice and inserted the isr in the vector table, but it doesn't work so far.

The PWM Signal runs blameless, but the ISR is never called. The LED should light up in the ISR.

Could you please take a look at my sources. Maybe you can find the mistake.

Thanks,

Andreas

[DavidS · Accepted solution]

Hi Andreas,

You commented out a printf() in the void enable_irq(int irq) routine that caused the div calculation to be in error (it pulled the div = irq/32; into the if statement).

if (irq > 91)

          //printf("\nERR! Invalid IRQ value passed to enable irq function!\n");

/* Determine which of the NVICISERs corresponds to the irq */

    div = irq/32;

Changing the code to:

if (irq > 91)

     asm(" nop"); //DES Must have an instruction after the "if() statement or using {} to indicate no instruction. With printf commented out div was not calculated correctly.

OR (better solution)

if (irq > 91)

{

//printf("\nERR! Invalid IRQ value passed to enable irq function!\n");

}

fixes the issue.

I also changed how the LED_PORT toggle was operating by following:

#define LED_PORT_T GPIOA_PTOR    //DES toggle port pin control

LED_PORT_T |= (1<<LED_GREEN);

Regards,

David

[andreasfrüchtl]

Oh crap, what a bad mistake. my professor would kill me. I will try this tomorrow.Everything is going to be allright :smileywink:

Many thanks for your assistance.

Best regards,

Andreas