How can I distinguish the reason for hardfault?

Question

Using SDK 7.2 and S110 7.1 
 
 
 IDE : IAR 7.1 
 
 
 Board : PCA10001 (Revision 2 MCU) 
 
 
 Hi, regardless of the example, when I add some codes of my own, 
 there are some cases when the firmware falls into HardFault_Handler 
 (or other Handlers such as BusFault_Handler). 
 
 Comparing to the situation such as SDK function returns error code, 
 it is easy for developers to tell what code is the problem. 
 Whereas when the code falls into HardFault_Handler, 
 is there a way to identify what cased this problem? 
 Added : 23, July, 2015 
 
 One more thing, do I have to consider the endian? 
 Since nRF51822-QFAA is based on little-endian, 
 is [0X2000 32D0] = 0x0001 0000 or 0x0100 0000 ? 
 If it's 0x0001 0000 (code instruction at 0x0001 0018 ), then this means the SoftDevice has caused a HardFault? 
 In my case, as mentioned above, I use SoftDevice S110 7.1 and SDK 7.2. 
 
 This is the Dissembly window. 
 (If showing the instructions of the SoftDevice is illegal, please notice me and I will edit this part.) 
 Also, this is a part of the .map file. 
 Section Kind Address Size Object
 ------- ---- ------- ---- ------
"A1": 0xc0
 .intvec ro code 0x00016000 0xc0 iar_startup_nrf51.o [1]
 - 0x000160c0 0xc0
 
"P1": 0x7c00
 
 .text ro code 0x000160c0 0xf14 device_manager_peripheral.o [1]
 .text ro code 0x00016fd4 0x28 memcmp.o [4]
 .text ro code 0x00016ffc 0x64 ABImemset.o [4]
 .text ro code 0x00017060 0x5c ABImemcpy.o [4]
 .text ro code 0x000170bc 0x8cc pstorage.o [1]
 .text ro code 0x00017988 0xe0 I32DivModFast.o [4]
 .text ro code 0x00017a68 0x2 IntDivZer.o [4]
 .text ro code 0x00017a6a 0x2a zero_init3.o [4]
 
 Added again : 23, July, 2015 
 
 @RK : At 0x00019b5a, it was LDR command. 
 -Regards

RK · Accepted Answer

Doing it as an answer even though it's not because the comments are restricted to about 2 lines! 
 01 00 00 00 in little endian is neither of the above, it's 0x00000001. Anyway that's not where you came from. 
 SP is 0x200032D0, so the return PC at exception time is stacked at that +0x18 = 0x200032E8 which has contents 0x00019b5a. 
 The link register is 0xFFFFFFF1 which means return to handler, which means you hardfaulted inside an interrupt handler .. but which one. 
 The word after the PC is at 0x200032EC and is 0x01000021, that's the PSP. Bit 24 is set telling you you came from Thumb mode, well we knew that. The lower 5 bits are 0x21 which is 33 which is the number of the interrupt being processed. Interrupts start at '1' for the reset handler, the first user interrupt is 16 so this is user interrupt ( 33 - 16 ) = 17. Interrupt 17 is RTC1. 
 So it looks like there was something which caused a hardfault inside some code called by the RTC1 interrupt handler (ie I guess a timer) the instruction causing the fault was at 0x00019b5a. 
 I'll hazard a wild guess that instruction turns out to be SVC .. see if I'm right.

How can I distinguish the reason for hardfault?

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