Dear Sir,
I have simulated the below code in IAR.
And it worked!
But I run this code in real KE02.
this code will cause KE02 reset.
could you help find out root cause?
I have changed the macro as below. this macro worked normally.
#define Set16Int(p,d) *(p)=d&0xff; *(p+1)=d>>8
====================================================
#define Get16Int(p) *((uint16*)(p))
#define Set16Int(p,d) *((uint16*)(p)) = d
uint16 u16gT=0;
uint8 u8gRxBuff[16];
u8gRxBuff[0]=0x12;
u8gRxBuff[1]=0x34;
u16gT = Get16Int(u8gRxBuff);
u16gT=0x1234;
Set16Int(
u8gRxBuff,u16gT);
Allen
The KE02 has a Cortex-m0+ core and this can only access aligned words.
Your code may or may not work, depending on the alignment of uint8 u8gRxBuff[16];
Take a look in the map file and you will presumably find that this is aligned on an odd address, which will cause
u16gT = Get16Int(u8gRxBuff);
to hard fault.
You either need to align you arrays (eg. use uint16 u8gRxBuff[16/sizeof(unsigned short)]; to force it) instead or else use macros which are core independent: eg. #define Get16Int(x) ((*(uint8*)x << 8) | (*(uint8*)((uint8 *)(x + 1))))
The IAR simulation may have been OK if you luckily had an even address, or possibly the IAR simulator is not checking correctly (test by passing u8gRxBuff + 1 instead to see whether it flags an illegal access).
Regards
Mark
http://www.utasker.com/kinetis.html
http://www.utasker.com/kinetis/FRDM-KE02Z.html
http://www.utasker.com/kinetis/FRDM-KE02Z40M.html
Allen
I gave this possibility in the previous post (although it may not be respected by all compilers):
uint16 u8gRxBuff[16/sizeof(unsigned short)];
Others are
uint8 u8gRxBuff[16 + 1];
uint8 *ptru8gRxBuff = u8gRxBuff;
if (((unsigned long)ptru8gRxBuff & 0x1) != 0) { // if not short word aligned
ptru8gRxBuff ++; // skip the first byte so that it is aligned
}
// Use ptru8gRxBuff for all operations (it is aligned memory)
uint8 *ptru8gRxBuff = malloc(16); // assuming a version of malloc() that always returns long word aligned memory
Regards
Mark
