This discussion has been locked.

You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Data abort handler in Cortex M4

Hi,
I wanted to know is there away to simulate data abort handler in cortex M4, I wanted to run some bin images from third party libraries, so I wanted to capture the data access to certain memory areas and replace the required answers to them to some custom error data that I want.

Parents

0 mike morgen over 6 years ago in reply to Westonsupermare Pier

I have managed to trap the memfault, but if I try to use it more than once, the next time I access the violaing memory, it would generate hardfault!!!

See the code

#include "LPC43xx.h"                    // Device header

int i=0;
int main(void)
{
    static int test;

        MPU->RNR = 0;//indicate MPU region 0
        MPU->RBAR = 0x00000000; // update the base address for the region 0
        MPU->RASR = 0x0307003F;
        test = MPU->RASR;

        MPU->RNR = 6;
        MPU->RBAR = 0x20080000; // update the base address for the region 6
        MPU->RASR = 0x0007001B;

        i = MPU->RASR;

        SCB->SHCSR |=(1<<16); //Enable Memory management fault
        MPU->CTRL |= 1;//enable MPU

    for(i=0;i<10;i++)
    {
        test = (*(unsigned int *)0x20080000);
    }

    while(1)
    {
        i++;

    }

}

__asm void __setPsp();
int value;
void HardFault_Handler (void)
{
    int r1;
    value=r1;

__setPsp();

}

__asm void __setPsp()
{
        add r13,32
        ldr r14,[r13]
        add r14,#2
        mov r0,#0
        MSR IPSR,r0
        mov r15,r14
}

void MemManage_Handler(void)
{
        __setPsp();
}

Isn't it suppose to generate memfault again?

Reply

0 mike morgen over 6 years ago in reply to Westonsupermare Pier

I have managed to trap the memfault, but if I try to use it more than once, the next time I access the violaing memory, it would generate hardfault!!!

See the code

#include "LPC43xx.h"                    // Device header

int i=0;
int main(void)
{
    static int test;

        MPU->RNR = 0;//indicate MPU region 0
        MPU->RBAR = 0x00000000; // update the base address for the region 0
        MPU->RASR = 0x0307003F;
        test = MPU->RASR;

        MPU->RNR = 6;
        MPU->RBAR = 0x20080000; // update the base address for the region 6
        MPU->RASR = 0x0007001B;

        i = MPU->RASR;

        SCB->SHCSR |=(1<<16); //Enable Memory management fault
        MPU->CTRL |= 1;//enable MPU

    for(i=0;i<10;i++)
    {
        test = (*(unsigned int *)0x20080000);
    }

    while(1)
    {
        i++;

    }

}

__asm void __setPsp();
int value;
void HardFault_Handler (void)
{
    int r1;
    value=r1;

__setPsp();

}

__asm void __setPsp()
{
        add r13,32
        ldr r14,[r13]
        add r14,#2
        mov r0,#0
        MSR IPSR,r0
        mov r15,r14
}

void MemManage_Handler(void)
{
        __setPsp();
}

Isn't it suppose to generate memfault again?

Children

No data