Getting a Hard Fault Interrupt when accessing the UART0 registers using Processor Expert on KE02

[najinaufel]

Hi,

I hope I am posting in the right forum.

I have seen this issue on many threads. I learned how to pinpoint the offending address and found that it is the UART0 address.

I am using CW10.5 with FRDM-KE02Z board. I can access the GPIO with no issues but as soon as the first instruction on the PE-generated Init_UART0() routine is executed, I get the Hard Fault.

The UART0 registers seem to be initialized properly (I think):

/** UART - Peripheral register structure */

typedef struct UART_MemMap {

  uint8_t BDH;                                     /**< UART Baud Rate Register: High, offset: 0x0 */

  uint8_t BDL;                                     /**< UART Baud Rate Register: Low, offset: 0x1 */

  uint8_t C1;                                      /**< UART Control Register 1, offset: 0x2 */

  uint8_t C2;                                      /**< UART Control Register 2, offset: 0x3 */

  uint8_t S1;                                      /**< UART Status Register 1, offset: 0x4 */

  uint8_t S2;                                      /**< UART Status Register 2, offset: 0x5 */

  uint8_t C3;                                      /**< UART Control Register 3, offset: 0x6 */

  uint8_t D;                                       /**< UART Data Register, offset: 0x7 */

} volatile *UART_MemMapPtr;

...

/* UART - Register accessors */

#define UART_BDH_REG(base)                       ((base)->BDH)

...

/* UART - Peripheral instance base addresses */

/** Peripheral UART0 base pointer */

#define UART0_BASE_PTR                           ((UART_MemMapPtr)0x4006A000u)

...

#define UART0_BDH                                UART_BDH_REG(UART0_BASE_PTR)

...

The instruction that fails is:

  UART0_C2 &= (uint8_t)~(uint8_t)((UART_C2_TE_MASK | UART_C2_RE_MASK));                                  

showing that the faulty address is 0x4006A000 which is the address of the UART0_BDH register.

Is this a bug in CW 10.5?

Thank you

[mjbcswitzerland]

Hi

Check whether the clock has been enabled to the UART before accesses are made to it:

UART0 bit in register SIM_SCGC

Regards

Mark

[najinaufel]

Hi Mark,

That was it!

Thank you

Naji Naufel

Sr. FAE

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naji.naufel@avnet.com

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