DSP6657 GPIO中断学习（只支持GPIO0-15）
1 简介
使用创龙板卡的KEY2按键通过中断的方式控制LED3的亮灭
2 中断学习
在C665x设备上，CPU中断是通过C66x CorePac中断控制器进行配置的。该中断控制器允许最多128个系统事件被编程到任意12个CPU可屏蔽中断输入（CPUINT4至CPUINT15）、CPU异常输入（EXCEP）或高级仿真逻辑中。这128个系统事件包括了内部生成的事件（在CorePac内）和芯片级事件。
此实验将事件91通过中断控制器连接到可屏蔽中断CPUINT12达到目的。
3 参考代码
main.c
#include <stdio.h>
/* Compiler Header files */
#include <stdint.h>
/* CSL Header file */
#include <ti/csl/csl_chipAux.h>
#include <ti/csl/src/intc/csl_intc.h>/* Driver utilities include */
#include "driver/c66x_gpio.h"#define PIN_CONTROL_0 0x02620580 // GPIO控制寄存器基地址
#define LED1 GPIO_19
#define LED2 GPIO_22
#define LED3 GPIO_23
#define KEY2 GPIO_0/* INTC Objects */
CSL_IntcObj gpioIntcObj;
CSL_IntcContext context;
CSL_IntcEventHandlerRecord EventHandler[30];static void test_isr_handler (void *arg)
{printf("succeeded!\n");if (gpio_read_input(KEY2) == GPIO_LOW)//按键真的被按下了{if (gpio_read_input(LED3) == GPIO_LOW) //LED3翻转gpio_set_output(LED3);//GPIO23设置为高电平，LED3熄灭elsegpio_clear_output(LED3);//GPIO23设置为低电平，LED3点亮}
}int Interrupts_Init(void)
{CSL_IntcGlobalEnableState state;CSL_Status intStat;CSL_IntcEventHandlerRecord EventRecord;CSL_IntcParam vectId;CSL_IntcHandle gpioIntcHandle;/* INTC module initialization */context.eventhandlerRecord = EventHandler;context.numEvtEntries = 1 ;//中断个数if (CSL_intcInit(&context) != CSL_SOK)return -1;/* Enable NMIs */if (CSL_intcGlobalNmiEnable() != CSL_SOK)return -1;/* Enable global interrupts */intStat = CSL_intcGlobalEnable(&state);/* Open INTC */vectId = CSL_INTC_VECTID_12;//此处选择使用十二个可屏蔽中断gpioIntcHandle = CSL_intcOpen(&gpioIntcObj, CSL_GEM_GPINTN, &vectId, &intStat);//第二项参数为128个中断事件的某一个，此处为事件91if (gpioIntcHandle == NULL)return -1;/* Bind ISR to Interrupt */EventRecord.handler = (CSL_IntcEventHandler)&test_isr_handler;//此处关联中断处理函数EventRecord.arg = gpioIntcHandle;CSL_intcPlugEventHandler(gpioIntcHandle, &EventRecord);/* Event Enable */CSL_intcHwControl(gpioIntcHandle, CSL_INTC_CMD_EVTENABLE, NULL);gpio_enable_global_interrupt();gpio_set_fallingedge_interrupt(KEY2);printf("interrupt init succeeded!\n");return 0;
}//基于CPU周期的延迟函数，100000000=100ms
void cpu_delaycycles(uint32_t cycles) {uint32_t start_val;/* Start TCSL so its free running */CSL_chipWriteTSCL(0);start_val = CSL_chipReadTSCL();while ((CSL_chipReadTSCL() - start_val) < cycles);
}int main(void) {/* Set pin as GPIO mode */*((uint32_t *) PIN_CONTROL_0) |= ((1 << LED1)|(1 << LED2) |(1 << KEY2 ) |(1 << LED3));/* Set GPIO as output mode */gpio_set_direction(LED1, GPIO_OUT);gpio_set_direction(LED2, GPIO_OUT);gpio_set_direction(LED3, GPIO_OUT);gpio_set_direction(KEY2, GPIO_IN);Interrupts_Init();while (1) ;
}
6657.cmd
-heap 0x4000/* 16KB */
-stack 0x4000/* 16KB */MEMORY
{/** L2SRAM Core internal address* if other cores or peripherals access, change to global address* Core 0: 0x10800000 ~ 0x1087FFFF* Core 1: 0x11800000 ~ 0x1187FFFF (only C6657)*/L2SRAM o = 0x00800000 l = 0x00100000 /* 1MB L2SRAM *//* Core0 running IBL will take up 0x0C000000 ~ 0x0C01FFFF(128KB), reserve at here! */MSMCSRAM o = 0x0C020000 l = 0x000E0000 /* 896KB MSMCSRAM */DDR3 o = 0x80000000 l = 0x20000000 /* 512MB DDR3 */}SECTIONS
{.text:_c_int00 > L2SRAM /* program entry address */.text > L2SRAM /* executable code */.cinit > L2SRAM /* tables which initialize global variables */.const > L2SRAM /* initialized global constant */.switch > L2SRAM /* jump tables for certain switch statements */.stack > L2SRAM /* system stack */.data > L2SRAM /* initialized global data */.far > L2SRAM /* far initialized global constant */.fardata > L2SRAM /* far uninitialized global and global variables */.cio > L2SRAM /* buffer for stdio functions */.sysmem > L2SRAM /* malloc heap */GROUP{.neardata /* far uninitialized global and global variables */.rodata /* global static constant */.bss /* uninitialized global variables*/} > L2SRAM
}