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STM32文档中关于NVIC寄存器说明的位置

来源:果壳中的宇宙博客  发布日期:2012-09-13 13:56:51

要使用STM32,需要各种文档,其中有(以STM32F103RBT6为例):

st官方资源地址:http://www.st.com/internet/mcu/product/164487.jsp

1、datasheet:http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00161566.pdf

2、REFERENCE MANUALS:http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/REFERENCE_MANUAL/CD00171190.pdf

3、ERRATA SHEETS:http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/ERRATA_SHEET/CD00190234.pdf

4、STM32F10x standard peripheral library:http://www.st.com/internet/com/SOFTWARE_RESOURCES/SW_COMPONENT/FIRMWARE/stm32f10x_stdperiph_lib.zip

ARM官方:

5、Cortex-M3 Technical Reference Manual Revision r1p1:http://infocenter.arm.com/help/topic/com.arm.doc.ddi0337e/DDI0337E_cortex_m3_r1p1_trm.pdf

6、ARMv7M Architecture Reference Manual:http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0403c/index.html

非官方的

The Definitive Guide to the ARM Cortex-M3(中文名:Cortex-M3 权威指南),虽然非官方,但很权威

 下面,我们看看关于NVIC寄存器的描述,都在哪些手册里面有提到

在使用STM32F10x standard peripheral library写有关于stm32中断的程序的时候,需要开启某个特定中断的控制位,除了对应外设的寄存器之外,还需要设置NVIC的相关寄存器的对应位。例如:


/******  STM32 specific Interrupt Numbers *********************************************************/
  WWDG_IRQn                   = 0,      /*!< Window WatchDog Interrupt                            */
  PVD_IRQn                    = 1,      /*!< PVD through EXTI Line detection Interrupt            */
  TAMPER_IRQn                 = 2,      /*!< Tamper Interrupt                                     */
  RTC_IRQn                    = 3,      /*!< RTC global Interrupt                                 */
  FLASH_IRQn                  = 4,      /*!< FLASH global Interrupt                               */
  RCC_IRQn                    = 5,      /*!< RCC global Interrupt                                 */
  EXTI0_IRQn                  = 6,      /*!< EXTI Line0 Interrupt                                 */
  EXTI1_IRQn                  = 7,      /*!< EXTI Line1 Interrupt                                 */
  EXTI2_IRQn                  = 8,      /*!< EXTI Line2 Interrupt                                 */
  EXTI3_IRQn                  = 9,      /*!< EXTI Line3 Interrupt                                 */
  EXTI4_IRQn                  = 10,     /*!< EXTI Line4 Interrupt                                 */
  DMA1_Channel1_IRQn          = 11,     /*!< DMA1 Channel 1 global Interrupt                      */
  DMA1_Channel2_IRQn          = 12,     /*!< DMA1 Channel 2 global Interrupt                      */
  DMA1_Channel3_IRQn          = 13,     /*!< DMA1 Channel 3 global Interrupt                      */
  DMA1_Channel4_IRQn          = 14,     /*!< DMA1 Channel 4 global Interrupt                      */
  DMA1_Channel5_IRQn          = 15,     /*!< DMA1 Channel 5 global Interrupt                      */
  DMA1_Channel6_IRQn          = 16,     /*!< DMA1 Channel 6 global Interrupt                      */
  DMA1_Channel7_IRQn          = 17,     /*!< DMA1 Channel 7 global Interrupt                      */

    NVIC_InitStructure.NVIC_IRQChannel = DMA1_Channel1_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

而NVIC_Init()这个函数:


/**
  * @brief  Initializes the NVIC peripheral according to the specified
  *         parameters in the NVIC_InitStruct.
  * @param  NVIC_InitStruct: pointer to a NVIC_InitTypeDef structure that contains
  *         the configuration information for the specified NVIC peripheral.
  * @retval None
  */ www.it165.net
void NVIC_Init(NVIC_InitTypeDef* NVIC_InitStruct)
{
  uint32_t tmppriority = 0x00, tmppre = 0x00, tmpsub = 0x0F;
  
  /* Check the parameters */
  assert_param(IS_FUNCTIONAL_STATE(NVIC_InitStruct->NVIC_IRQChannelCmd));
  assert_param(IS_NVIC_PREEMPTION_PRIORITY(NVIC_InitStruct->NVIC_IRQChannelPreemptionPriority));  
  assert_param(IS_NVIC_SUB_PRIORITY(NVIC_InitStruct->NVIC_IRQChannelSubPriority));
    
  if (NVIC_InitStruct->NVIC_IRQChannelCmd != DISABLE)
  {
    /* Compute the Corresponding IRQ Priority --------------------------------*/    
    tmppriority = (0x700 - ((SCB->AIRCR) & (uint32_t)0x700))>> 0x08;
    tmppre = (0x4 - tmppriority);
    tmpsub = tmpsub >> tmppriority;

    tmppriority = (uint32_t)NVIC_InitStruct->NVIC_IRQChannelPreemptionPriority << tmppre;
    tmppriority |=  NVIC_InitStruct->NVIC_IRQChannelSubPriority & tmpsub;
    tmppriority = tmppriority << 0x04;
        
    NVIC->IP[NVIC_InitStruct->NVIC_IRQChannel] = tmppriority;
    
    /* Enable the Selected IRQ Channels --------------------------------------*/
    NVIC->ISER[NVIC_InitStruct->NVIC_IRQChannel >> 0x05] =
      (uint32_t)0x01 << (NVIC_InitStruct->NVIC_IRQChannel & (uint8_t)0x1F);
  }
  else
  {
    /* Disable the Selected IRQ Channels -------------------------------------*/
    NVIC->ICER[NVIC_InitStruct->NVIC_IRQChannel >> 0x05] =
      (uint32_t)0x01 << (NVIC_InitStruct->NVIC_IRQChannel & (uint8_t)0x1F);
  }
}

可以看到,它会去设置几个寄存器:NVIC的IP,ISER,ICER等等,NVIC是基址,为:


#define SCS_BASE            (0xE000E000)                              /*!< System Control Space Base Address */
#define NVIC_BASE           (SCS_BASE +  0x0100)                      /*!< NVIC Base Address                 */
#define SCB_BASE            (SCS_BASE +  0x0D00)                      /*!< System Control Block Base Address */


#define NVIC                ((NVIC_Type *)          NVIC_BASE)        /*!< NVIC configuration struct         */

NVIC_Type为:


/** @addtogroup CMSIS_CM3_NVIC CMSIS CM3 NVIC
  memory mapped structure for Nested Vectored Interrupt Controller (NVIC)
  @{
 */
typedef struct
{
  __IO uint32_t ISER[8];                      /*!< Offset: 0x000  Interrupt Set Enable Register           */
       uint32_t RESERVED0[24];                                   
  __IO uint32_t ICER[8];                      /*!< Offset: 0x080  Interrupt Clear Enable Register         */
       uint32_t RSERVED1[24];                                    
  __IO uint32_t ISPR[8];                      /*!< Offset: 0x100  Interrupt Set Pending Register          */
       uint32_t RESERVED2[24];                                   
  __IO uint32_t ICPR[8];                      /*!< Offset: 0x180  Interrupt Clear Pending Register        */
       uint32_t RESERVED3[24];                                   
  __IO uint32_t IABR[8];                      /*!< Offset: 0x200  Interrupt Active bit Register           */
       uint32_t RESERVED4[56];                                   
  __IO uint8_t  IP[240];                      /*!< Offset: 0x300  Interrupt Priority Register (8Bit wide) */
       uint32_t RESERVED5[644];                                  
  __O  uint32_t STIR;                         /*!< Offset: 0xE00  Software Trigger Interrupt Register     */
}  NVIC_Type;                                               
/*@}*/ /* end of group CMSIS_CM3_NVIC */

从上面可以了解到的是,NVIC的寄存器的基址是没有错的,《The Definitive Guide to the ARM Cortex-M3》 85页有个比较详细的内存图;或者查看《Cortex-M3 Technical Reference Manual Revision r1p1》3.4 System address map,6.3 NVIC programmers model:


 

以及:


 

以及ARMv7-M Architecture Reference Manual中,B3.4 Nested Vectored Interrupt Controller (NVIC)的相关说明,例如:


 

当然,你看权威指南也可以的,在其APPENDIX D:NVIC Registers Quick Reference里面也有所描述。

但还有一个问题,我怎么知道这个Interrupt Set-Enable Registers寄存器的哪个位对应哪个中断呢?例如NVIC_ISER0的第0位对应哪个呢,其实,上面的表B3-31的说明已经说了,每一位对应一个中断号,所以我们还得看看stm32F103对应的中断号,可以查阅《RM0008:Reference manual》的第10章,Interrupts and events中的中断向量表,找到对应MD容量的那个表Table 63. Vector table for other STM32F10xxx devices,前面16个M3内核的中断,不可以从这个寄存器里控制,所以不管,我们从WWDG开始,可以看到这个表中的第一列即对应于寄存器中的某位(超过31的自己换算一下即可):


 

可以看到,STM32F10x standard peripheral library文件stm32f10x.h中的中断号的定义是能够与这里对应上的。

另外,stm32F103RB的Datasheet(CD00161566)里面的2.3.5 Nested vectored interrupt controller (NVIC)提到F103仅有43个可屏蔽中断,所以只需用到NVIC_ISER0和NVIC_ISER1来设置启用外设中断。

【The STM32F103xx performance line embeds a nested vectored interrupt controller able to handle up to 43 maskable interrupt channels (not including the 16 interrupt lines of Cortex™-M3) and 16 priority levels.】

得查阅这么多文档,才能知道这个Interrupt Set-Enable Registers寄存器在哪里有描述,怎么设置,文档很分散。这些文档估计是程序员组织的,呵呵。因为像这些M3内核的相关模块,与外设无关的,只要是M3内核的器件都是通用的,所以不用每个器件的手册都带,这样比较节省空间,⊙﹏⊙b汗

所以,以后要是涉及到M3内核相关的,都得去查阅《M3权威指南》或者官方的《Cortex-M3 Technical Reference Manual》以及《ARMv7M Architecture Reference Manual》。


Tag标签: STM32   NVIC寄存器  
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