iar环境下，uCosII在stm32下的运行机理是怎样的？

tankli01 2009-2-13 11:15 楼主

编译器的iar EWARM，
uCosII 通过初始化下面的向量表，在程序复位时将程序定位到__program_start（void)函数，但该函数是个空函数呀，程序到底是怎么进行到正常状态的呢？请大虾们指点。

另外，向量表__vector_table[] 的第一行{ .__ptr = __sfe( "CSTACK" ) },是什么意思呀？
下面是uCosII 自带的向量初始化文件‘app_vect.c’的完整内容：

/******************** (C) COPYRIGHT 2008 STMicroelectronics ********************
* File Name          : stm32f10x_vector.c
* Author             : MCD Application Team
* Version            : V2.0.3
* Date               : 09/22/2008
* Description        : STM32F10x vector table for EWARM4.x toolchain.
*                      This module performs:
*                      - Set the initial SP
*                      - Set the initial PC == __program_start,
*                      - Set the vector table entries with the exceptions ISR address,
*                     - Configure external SRAM mounted on STM3210E-EVAL board
*                       to be used as data memory (optional, to be enabled by user)
*                      After Reset the Cortex-M3 processor is in Thread mode,
*                      priority is Privileged, and the Stack is set to Main.
********************************************************************************
* THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
* WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE TIME.
* AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY DIRECT,
* INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING FROM THE
* CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE CODING
* INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
*******************************************************************************/

/* Includes ------------------------------------------------------------------*/
#include "stm32f10x_lib.h"
#include "stm32f10x_it.h"

/* Private typedef -----------------------------------------------------------*/
typedef void( *intfunc )( void );
typedef union { intfunc __fun; void * __ptr; } intvec_elem;

/* Private define ------------------------------------------------------------*/
/* Uncomment the following line if you need to use external SRAM mounted on
   STM3210E-EVAL board as data memory */

/* #define DATA_IN_ExtSRAM */

/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/

#pragma language=extended
#pragma segment="CSTACK"

void __program_start( void );

#pragma location = "INTVEC"
/* STM32F10x Vector Table entries */
const intvec_elem __vector_table[] =
{
  { .__ptr = __sfe( "CSTACK" ) },
  __program_start,
  NMIException,
  HardFaultException,
  MemManageException,
  BusFaultException,
  UsageFaultException,
  0, 0, 0, 0,            /* Reserved */
  SVCHandler,
  DebugMonitor,
  0,                      /* Reserved */
  PendSVC,
  SysTickHandler,
  WWDG_IRQHandler,
  PVD_IRQHandler,
  TAMPER_IRQHandler,
  RTC_IRQHandler,
  FLASH_IRQHandler,
  RCC_IRQHandler,
  EXTI0_IRQHandler,
  EXTI1_IRQHandler,
  EXTI2_IRQHandler,
  EXTI3_IRQHandler,
  EXTI4_IRQHandler,
  DMA1_Channel1_IRQHandler,
  DMA1_Channel2_IRQHandler,
  DMA1_Channel3_IRQHandler,
  DMA1_Channel4_IRQHandler,
  DMA1_Channel5_IRQHandler,
  DMA1_Channel6_IRQHandler,
  DMA1_Channel7_IRQHandler,
  ADC1_2_IRQHandler,
  USB_HP_CAN_TX_IRQHandler,
  USB_LP_CAN_RX0_IRQHandler,
  CAN_RX1_IRQHandler,
  CAN_SCE_IRQHandler,
  EXTI9_5_IRQHandler,
  TIM1_BRK_IRQHandler,
  TIM1_UP_IRQHandler,
  TIM1_TRG_COM_IRQHandler,
  TIM1_CC_IRQHandler,
  TIM2_IRQHandler,
  TIM3_IRQHandler,
  TIM4_IRQHandler,
  I2C1_EV_IRQHandler,
  I2C1_ER_IRQHandler,
  I2C2_EV_IRQHandler,
  I2C2_ER_IRQHandler,
  SPI1_IRQHandler,
  SPI2_IRQHandler,
  USART1_IRQHandler,
  USART2_IRQHandler,
  USART3_IRQHandler,
  EXTI15_10_IRQHandler,
  RTCAlarm_IRQHandler,
  USBWakeUp_IRQHandler,
  TIM8_BRK_IRQHandler,
  TIM8_UP_IRQHandler,
  TIM8_TRG_COM_IRQHandler,
  TIM8_CC_IRQHandler,
  ADC3_IRQHandler,
  FSMC_IRQHandler,
  SDIO_IRQHandler,
  TIM5_IRQHandler,
  SPI3_IRQHandler,
  UART4_IRQHandler,
  UART5_IRQHandler,
  TIM6_IRQHandler,
  TIM7_IRQHandler,
  DMA2_Channel1_IRQHandler,
  DMA2_Channel2_IRQHandler,
  DMA2_Channel3_IRQHandler,
  DMA2_Channel4_5_IRQHandler,
};
#ifdef DATA_IN_ExtSRAM
#pragma language=extended

__interwork int __low_level_init(void);

#pragma location="ICODE"
__interwork int __low_level_init(void)
{

/* FSMC Bank1 NOR/SRAM3 is used for the STM3210E-EVAL, if another Bank is
  required, then adjust the Register Addresses*/

  /* Enable FSMC clock */
  *(vu32 *)0x40021014 = 0x00000114;

  /* Enable GPIOD, GPIOE, GPIOF and GPIOG clocks */
  *(vu32 *)0x40021018 = 0x000001E0;

/* ---------------  SRAM Data lines, NOE and NWE configuration ---------------*/
/*----------------  SRAM Address lines configuration -------------------------*/
/*----------------  NOE and NWE configuration --------------------------------*/
/*----------------  NE3 configuration ----------------------------------------*/
/*----------------  NBL0, NBL1 configuration ---------------------------------*/

  *(vu32 *)0x40011400 = 0x44BB44BB;
  *(vu32 *)0x40011404 = 0xBBBBBBBB;

  *(vu32 *)0x40011800 = 0xB44444BB;
  *(vu32 *)0x40011804 = 0xBBBBBBBB;

  *(vu32 *)0x40011C00 = 0x44BBBBBB;
  *(vu32 *)0x40011C04 = 0xBBBB4444;

  *(vu32 *)0x40012000 = 0x44BBBBBB;
  *(vu32 *)0x40012004 = 0x44444B44;

/*----------------  FSMC Configuration ---------------------------------------*/
/*----------------  Enable FSMC Bank1_SRAM Bank ------------------------------*/

  *(vu32 *)0xA0000010 = 0x00001011;
  *(vu32 *)0xA0000014 = 0x00000200;


  return (1);
}
#endif /*DATA_IN_ExtSRAM*/

/******************* (C) COPYRIGHT 2008 STMicroelectronics *****END OF FILE****/