Nested Vectored Interrupt Controller (NVIC)

包含在Cortex-M4F 中，

优先级有16级

中断相关寄存器

ISER[0-3]:Interrupt Set Enable Register

ICER[0-3]:Interrupt Clear Enable Register

ISPR[0-3]:Interrupt Set Pending Register

ICPR[0-3]:Interrupt Clear Pending Register

IABR[0-3]:Interrupt Active bit Register

IP[0-122]:Interrupt Priority Register

STIR:Software Trigger Interrupt Register

以外部中断PORTC_IRQn 为例

查看S32K1xx_DMA_INT_mapping.xlsm

屏幕剪辑的捕获时间: 2019/8/4 6:59

第三列 NVIC Interrupt ID 表示中断号

第四列 ISER, ICER, ISPR, ICPR, and IABR 寄存器号，等于NVIC Interrupt ID 整除32

第五列 IPR寄存器号 *实际为每个寄存器存4个中断源优先级，程序已经分开定义成了0-122 直接IPR[NVIC interrupt ID]即可

初始化时在应用模块配置好后（如外部中断需要在PCR中配置IRQC），加下以下NVIC 配置

S32_NVIC->ICPR[PORTC_IRQn/32] = 1 << (PORTC_IRQn % 32); /* clr any pending IRQ*/

S32_NVIC->ISER[PORTC_IRQn/32] = 1 << (PORTC_IRQn % 32); /* enable IRQ */

S32_NVIC->IP[PORTC_IRQn] = 0xA0; /* priority 10 of 0-15*/

中断程序写对应用.s 里中断指向的程序

void PORTC_IRQHandler (void) {

PORTC->ISFR=0xFFFFFFFFu;/* Clear button IRQ flag */

}

完整程序：

#include "S32K144.h" /* include peripheral declarations S32K144 */

#define PTD0 0 /* Port PTD0, bit 0: FRDM EVB output to blue LED */

#define PTC12 12 /* Port PTC12, bit 12: FRDM EVB input from BTN0 [SW2] */

void PORTC_IRQHandler (void) {

PORTC->ISFR=0xFFFFFFFFu;

/* Perform read-after-write to ensure flag clears before ISR exit */

PTD->PTOR |= 1<<0; /* Toggle output on port D0 (blue LED) */

}

int main(void) {

/* Enable clocks to peripherals (PORT modules) */

PCC-> PCCn[PCC_PORTC_INDEX] = PCC_PCCn_CGC_MASK; /* Enable clock to PORT C */

PCC-> PCCn[PCC_PORTD_INDEX] = PCC_PCCn_CGC_MASK; /* Enable clock to PORT D */

/* Configure port C12 as GPIO input (BTN 0 [SW2] on EVB) */

PORTC->DFCR=1;                                //Digital Filter Clock=LPO

PORTC->DFWR=8;                                //Digital Filter width=8

PORTC->DFER=1<<PTC12;                        //Enable Digital Filter

PTC->PDDR &= ~(1<<PTC12); /* Port C12: Data Direction= input (default) */

PORTC->PCR[12] = 0x00090110; /* Port C12: MUX = GPIO, input filter enabled，Interrupt on rising edge */

S32_NVIC->ICPR[PORTC_IRQn/32] = 1 << (PORTC_IRQn % 32); /* clr any pending IRQ*/

S32_NVIC->ISER[PORTC_IRQn/32] = 1 << (PORTC_IRQn % 32); /* enable IRQ */

S32_NVIC->IP[PORTC_IRQn] = 0xA0; /* priority 10 of 0-15*/

/* Configure port D0 as GPIO output (LED on EVB) */

PTD->PDDR |= 1<<PTD0; /* Port D0: Data Direction= output */

PORTD->PCR[0] = 0x00000100; /* Port D0: MUX = GPIO */

for(;;) {

}

}