topic MK10DN128VFT5 fires ISR7 in Kinetis Microcontrollers

MK10DN128VFT5 fires ISR7

korneliuszosmen — Thu, 26 Nov 2020 12:03:38 GMT

#define ISR(x) \ static void ISR_ ## x () \ { \ __asm volatile ("bkpt #0\n") ; \ } ISR(7) ISR(8) ISR(9) ISR(10) ISR(11) ISR(13) ISR(14) ISR(15) void (* const g_pfnVectors[])(void) = { // Core Level - CM3 (void *)&_vStackTop -1, // The initial stack pointer ResetISR, // The reset handler NMI_Handler, // The NMI handler HardFault_Handler, // The hard fault handler MemManage_Handler, // The MPU fault handler BusFault_Handler, // The bus fault handler UsageFault_Handler, // The usage fault handler ISR_7, // Reserved ISR_8, // Reserved ISR_9, // Reserved ISR_10, // Reserved // vPortSVCHandler, // SVCall handler ISR_11, DebugMon_Handler, // Debug monitor handler ISR_13, // Reserved // xPortPendSVHandler, // The PendSV handler ISR_14, // xPortSysTickHandler, // The SysTick handler ISR_15, //16 .....

I have such code and after second pass trough crt0 ISR_7 is fired. Can I safely ignore this interrupt or it shows some error in code which I should address? Reference manual of mcu says that this interrupt is reserved.

CRT0 does:

disables interrupts
disables watchdog
setup stack pointer
zero bss
fill stack with canar value
copy data to ram
copy isr table to ram
set pointer to isr table so they run from ram
enables fpu in CPACR
enables PORT clocks
setups clock from external RTC clock
NVIC_SetPriorityGrouping(0)
goes to main function which enables interrupts

Re: MK10DN128VFT5 fires ISR7

mjbcswitzerland — Thu, 26 Nov 2020 23:35:10 GMT

I have never heard of a reserved interrupt firing and don't think that there is any actual interrupt behind it.

If you are hitting this code it may be that your code is running into it (from another fault) so check the call-stack to see whether it is really arriving there from an interrupt and try stepping back out of the code/interrupt to see where it came from.

Regards

Mark
[uTasker project developer for Kinetis and i.MX RT]
Contact me by personal message or on the uTasker web site to discuss professional training, solutions to problems or product development requirements

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Re: MK10DN128VFT5 fires ISR7

korneliuszosmen — Fri, 27 Nov 2020 08:40:38 GMT

Backtrace:

(gdb) bt
#0 ISR_7 () at /<redacted>/crt0.c:291
#1 <signal handler called>
#2 main () at /<redacted>/main.cpp:71

main from line 65:

asm("CPSIE if"); //*(uint8_t *)0xFFFFFFFF = (1<<1); uint32_t zegar=3000000ul; volatile uint32_t i; for(i=0;i<zegar/4;i++);

Interrupt fires in busy loop

Re: MK10DN128VFT5 fires ISR7

Alexis_A — Mon, 30 Nov 2020 17:02:05 GMT

Hello @korneliuszosmen,

Usually, for the reserved interrupts, in the g_pfnVectors array is not define:

Best Regards,

Alexis Andalon

Re: MK10DN128VFT5 fires ISR7

korneliuszosmen — Tue, 01 Dec 2020 06:49:04 GMT

When I had ISR_7 not definied, I was getting HardFaults