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Physical and Virtual Address during debugging

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kanni1303

kanni1303

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Hi,
I came across a problem today here is my code

Code: 
#define NVMEM_ADDRS_PHY 0x1D07000     //Physical address
#define NVMEM_ADDRS_VIR 0xBD07000     //Virtual address

DWORD Flashval;
DWORD *Flashptr;
//Working to read the value
Flashptr= (DWORD *) NVMEM_ADDRS_VIR;
Flashval = (DWORD) *Flashptr;

//Not working but in watch it is working
Flashptr= (DWORD *) NVMEM_ADDRS_PHY;
Flashval = (DWORD) *Flashptr;
Nop();


the problem is using physical address I could write the data and during debugging the value was able to read( I kept break point on "Flashval = (DWORD) *Flashptr;" and on watches the data i wrote already was available, but after that line my controller resets)

I clearly know this is because of virtual and physical address issue, my question is during debugging how watch could read the value and why write was success but read was failed?
 

As a general rule of thumbs, although being perfectly possible, defining a physical address in C language is not a nice idea; Doing that, you are somehow competing with the compiler in allocating variables. It is better to let the linker do that for you. In addition, I would recommend to you debug variables content rather than adresses content.
 

andre_teprom said:
As a general rule of thumbs, although being perfectly possible, defining a physical address in C language is not a nice idea; Doing that, you are somehow competing with the compiler in allocating variables. It is better to let the linker do that for you. In addition, I would recommend to you debug variables content rather than adresses content.
Click to expand...

You didn't understood my question, I asked for why during debugging watch could able to read the memory value but controller not able to do?
 

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