Hi,
I have one question about Cortexm3 from smartfusion device from actel. Could you pls help me? I add follwing codes into retarget.c and then add retarget.c into source code group and find : printf function works.however scanf function doesn't. anybody knows why?
int fputc(int ch, FILE *f) { return ((int)ITM_SendChar(ch)); } int fgetc(FILE *f) { int i=0; i=ITM_ReceiveChar(); if((-1)!=i) return ((int)ITM_SendChar((uint32_t)i)); else return (0); }
printf("hello world\n\r"); // when executed, string displayed in debug(printf)window scanf("%s",str); // when executed, hard fault occurs
here, str is defined as an array.for example
unsigned char str[10];
So how do you ensure that the data returned by scanf doesn't exceed 9 characters (or whatever your array size happens to be) ?
Surely, this is a fundamental flaw with using scanf ?!
Try searching the forum for "scanf"...
hi, it is just a test since it is myself who is clicking the keyboard.
I don't know when the PC will point to hardfault handler once defined scanf function is executed.
I had searched "scanf" in this forum and find no similar thread.
Looking forward to help.
thanks.
Fisher
You missed the point!
The point is that scanf is, generally, a Bad Thing to be using in such a situation - there are plenty of threads that illustriate this point.
Did you ever implement success scanf function in Cortexm3 in smartFusion? I guess you didn't. otherwise you will find that those scanf examples found in another thereads don't work in Cortexm3 within smartFusion!
Why not?
Is it really anything specifically to do with Cortex-M3 and/or SmartFusion?
Could you please post your scanf() here? I know how to retarget to real UART connected to PC via Hypertermial using retarget.c. However I don't know how to retarget to debug(printf) windows via ITM.
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