转载：定位ARM Hard Fault 的方法

转载自：http://www.openedv.com/posts/list/25030.htm

1、用Keil的话，可以做如下操作：

先将fault中断函数的内容改为:

HardFault_Handler\
                PROC
                ;EXPORT  HardFault_Handler         [WEAK]
                ;B                  .
                                IMPORT hard_fault_handler_c
                                TST LR, #
                                ITE EQ
                                MRSEQ R0, MSP
                                MRSNE R0, PSP
                                B hard_fault_handler_c
                ENDP

然后在源程序里添加下面的函数代码:
// hard fault handler in C,
// with stack frame location as input parameter
void hard_fault_handler_c(unsigned int * hardfault_args)
{
unsigned int stacked_r0;
unsigned int stacked_r1;
unsigned int stacked_r2;
unsigned int stacked_r3;
unsigned int stacked_r12;
unsigned int stacked_lr;
unsigned int stacked_pc;
unsigned int stacked_psr;  

stacked_r0 = ((unsigned long) hardfault_args[]);
stacked_r1 = ((unsigned long) hardfault_args[]);
stacked_r2 = ((unsigned long) hardfault_args[]);
stacked_r3 = ((unsigned long) hardfault_args[]);  

stacked_r12 = ((unsigned long) hardfault_args[]);
stacked_lr = ((unsigned long) hardfault_args[]);
stacked_pc = ((unsigned long) hardfault_args[]);
stacked_psr = ((unsigned long) hardfault_args[]);  

printf ("[Hard fault handler]\n");
printf ("R0 = %x\n", stacked_r0);
printf ("R1 = %x\n", stacked_r1);
printf ("R2 = %x\n", stacked_r2);
printf ("R3 = %x\n", stacked_r3);
printf ("R12 = %x\n", stacked_r12);
printf ("LR = %x\n", stacked_lr);
printf ("PC = %x\n", stacked_pc);
printf ("PSR = %x\n", stacked_psr);
printf ("BFAR = %x\n", (*((volatile unsigned long *)(0xE000ED38))));
printf ("CFSR = %x\n", (*((volatile unsigned long *)(0xE000ED28))));
printf ("HFSR = %x\n", (*((volatile unsigned long *)(0xE000ED2C))));
printf ("DFSR = %x\n", (*((volatile unsigned long *)(0xE000ED30))));
printf ("AFSR = %x\n", (*((volatile unsigned long *)(0xE000ED3C))));  

while()
{
        ;;
}
}
 

2、用IAR的话，把startup_ewarm.c文件中的FaultISR（）函数的内容改为：

volatile unsigned int stacked_r0;
volatile unsigned int stacked_r1;
volatile unsigned int stacked_r2;
volatile unsigned int stacked_r3;
volatile unsigned int stacked_r12;
volatile unsigned int stacked_lr;
volatile unsigned int stacked_pc;
volatile unsigned int stacked_psr;  

//unsigned long cc;

stacked_r0 = ((unsigned long) hardfault_args[]);
stacked_r1 = ((unsigned long) hardfault_args[]);
stacked_r2 = ((unsigned long) hardfault_args[]);
stacked_r3 = ((unsigned long) hardfault_args[]);  

stacked_r12 = ((unsigned long) hardfault_args[]);
stacked_lr = ((unsigned long) hardfault_args[]);
stacked_pc = ((unsigned long) hardfault_args[]);
stacked_psr = ((unsigned long) hardfault_args[]);  

printf ("[Hard fault handler]\n");
printf ("R0 = %x\n", stacked_r0);
printf ("R1 = %x\n", stacked_r1);
printf ("R2 = %x\n", stacked_r2);
printf ("R3 = %x\n", stacked_r3);
printf ("R12 = %x\n", stacked_r12);
printf ("LR = %x\n", stacked_lr);
printf ("PC = %x\n", stacked_pc);
printf ("PSR = %x\n", stacked_psr);
printf ("BFAR = %x\n", (*((volatile unsigned long *)(0xE000ED38))));
printf ("CFSR = %x\n", (*((volatile unsigned long *)(0xE000ED28))));
printf ("HFSR = %x\n", (*((volatile unsigned long *)(0xE000ED2C))));
printf ("DFSR = %x\n", (*((volatile unsigned long *)(0xE000ED30))));
printf ("AFSR = %x\n", (*((volatile unsigned long *)(0xE000ED3C))));  

  while()
  {
          ;;
  }

如果使用调试器,则可以在第一个printf处设置断点。

没有的话看串口打印结果通过查看stacked_lr的内容可以知道程序运行到哪个位置出现fault，然后查看编译后汇编代码,可以知道源程序是哪个函数哪一步出现问题,配合其它寄存器的内容来分析找出原因。