学习内容

实现对GPIO的中断控制程序，实现按键按下使得led灯闪亮一次，并结合前文的IIC工程，实现按键控制iic的数据采集。

开发环境

vivado 18.3 SDK PYNQ-Z2

中断初始化的设置

对于熟悉ARM和32开发的人来说，中断的概念对其并不陌生。下面我给出按键在32开发时候的初始化的流程：按键中断编程步骤分析：

使能相应的时钟
配置GPIO管脚为中断功能
设置中断优先级
使能相应的中断
实现中断服务程序

然后我给出ZYNQ的中断初始化的设置流程：

初始化CPU异常功能
初始化中断控制器
向CPU注册异常处理回调函数
向中断控制器中对应的中断ID和中断控制器相连接
设置中断的类型
设置中断的回调函数（用户自己设置）
使能对应引脚的中断
使能中断控制器
使能异常处理功能

对比纯arm开发和zynq的开发，我们可以大致看出，两者在中断初始化的过程中有很多相似的地方。因为zynq的功能比较多，比较复杂，在开发的时的配置过程也相对麻烦。

对应初始化过程中的每一步，我们可以找到对应的函数进行调用，具体过程如下：

硬件平台搭建

新建工程初始化我们需要用到了GPIO的资源引脚，具体的工程可以参考ZYNQ-利用PS引脚实现EMIO GPIO的驱动这里只给出搭建后的结果：（这里只进行设计了gpio可以实现对应按键控制灯闪烁）

也可以同时把iic的模块进行设计，用于按键实现采集控制

综合生成bit流文件后，进行导出hardware，launch SDK

SDK软件部分

新建工程后，在main中添加中断初始化代码：

#define SCUGIC_0_ID XPAR_PS7_SCUGIC_0_DEVICE_ID
#define GPIO_INTR_ID 52
#define SW_BANK_ID 2
static XScuGic GicPs;
static XScuGic_Config *XScuGic_Cfg;

int setupinterrupt(){
	int status;
	//初始化异常处理
	Xil_ExceptionInit();
	//初始化中断控制器
	XScuGic_Cfg = XScuGic_LookupConfig(SCUGIC_0_ID);
	status = XScuGic_CfgInitialize(&GicPs,XScuGic_Cfg,XScuGic_Cfg->CpuBaseAddress);
	if( status != XST_SUCCESS){
			return XST_FAILURE;
	}
	//CPU中断异常注册
	Xil_ExceptionRegisterHandler(XIL_EXCEPTION_ID_INT,(Xil_ExceptionHandler)XScuGic_InterruptHandler,&GicPs);
	//链接中断信号
	status = XScuGic_Connect(&GicPs,GPIO_INTR_ID,(Xil_InterruptHandler)XGpioPs_IntrHandler,&GpioPs);
	if( status != XST_SUCCESS){
				return XST_FAILURE;
	}
	//中断类型设置
	XGpioPs_SetIntrType(&GpioPs,SW_BANK_ID,0xffffffff,0xffffffff,0x00);
	//设置中断回调函数
	XGpioPs_SetCallbackHandler(&GpioPs,(void *) &GpioPs, IntrHandler);
	//打开gpio中断
	XGpioPs_IntrEnable(&GpioPs,SW_BANK_ID,1<<(BTN1-54));
	XScuGic_Enable(&GicPs,GPIO_INTR_ID);
	Xil_ExceptionEnableMask(XIL_EXCEPTION_IRQ);
	return XST_SUCCESS;
}

对于部分参数的查找进行简单说明，具体函数的使用，可以参考system.mss中进行查找：==GPIO_INTR_ID== ：中断配置时，要对中断ID进行设置，否则对应不上配置的中断

==SW_BANK_ID== ：因为我们BANK0和BANK1对应的是MIO的管脚是54个，我们声明的管脚在BANK 2，所以我们就设置的BANK ID为2

按键控制led

#include 
#include "platform.h"
#include "xil_printf.h"
#include "xgpiops.h"
#include "xparameters.h"
#include "xscugic.h"

#define GPIO_ID XPAR_PS7_GPIO_0_DEVICE_ID
#define SCUGIC_0_ID XPAR_PS7_SCUGIC_0_DEVICE_ID
#define GPIO_INTR_ID 52
#define SW_BANK_ID 2
#define LED0 54
#define LED1 55
#define BTN1 56
static XGpioPs GpioPs;
static XGpioPs_Config *XGpioPs_Cfg;
static XScuGic GicPs;
static XScuGic_Config *XScuGic_Cfg;
int initGpio();
int setupinterrupt();
void IntrHandler(void *CallBack,u32 Bank,u32 status);
int main()
{
	init_platform();
    initGpio();
    print("Hello World\n\r");
    setupinterrupt();
    while(1)
    {
    	XGpioPs_WritePin(&GpioPs,LED0,0);
    	XGpioPs_WritePin(&GpioPs,LED1,0);

    	usleep(1000);

    }
    cleanup_platform();
    return0;
}
int initGpio(){
	int status;
	XGpioPs_Cfg = XGpioPs_LookupConfig(GPIO_ID);
	status = XGpioPs_CfgInitialize(&GpioPs,XGpioPs_Cfg,XGpioPs_Cfg->BaseAddr);
	if( status != XST_SUCCESS){
		return XST_FAILURE;
	}
	XGpioPs_SetDirectionPin(&GpioPs,LED0,0x01);
	XGpioPs_SetOutputEnablePin(&GpioPs,LED0,0x01);
	XGpioPs_SetDirectionPin(&GpioPs,LED1,0x01);
	XGpioPs_SetOutputEnablePin(&GpioPs,LED1,0x01);
	XGpioPs_SetDirectionPin(&GpioPs,BTN1,0x00);
	XGpioPs_SetOutputEnablePin(&GpioPs,BTN1,0x00);
}
int setupinterrupt(){
	int status;
	//初始化异常处理
	Xil_ExceptionInit();
	//初始化中断控制器
	XScuGic_Cfg = XScuGic_LookupConfig(SCUGIC_0_ID);
	status = XScuGic_CfgInitialize(&GicPs,XScuGic_Cfg,XScuGic_Cfg->CpuBaseAddress);
	if( status != XST_SUCCESS){
			return XST_FAILURE;
	}
	//CPU中断异常注册
	Xil_ExceptionRegisterHandler(XIL_EXCEPTION_ID_INT,(Xil_ExceptionHandler)XScuGic_InterruptHandler,&GicPs);
	//链接中断信号
	status = XScuGic_Connect(&GicPs,GPIO_INTR_ID,(Xil_InterruptHandler)XGpioPs_IntrHandler,&GpioPs);
	if( status != XST_SUCCESS){
				return XST_FAILURE;
	}
	//中断类型设置
	XGpioPs_SetIntrType(&GpioPs,SW_BANK_ID,0xffffffff,0xffffffff,0x00);
	//设置中断回调函数
	XGpioPs_SetCallbackHandler(&GpioPs,(void *) &GpioPs, IntrHandler);
	//打开gpio中断
	XGpioPs_IntrEnable(&GpioPs,SW_BANK_ID,1<<(BTN1-54));
	XScuGic_Enable(&GicPs,GPIO_INTR_ID);
	Xil_ExceptionEnableMask(XIL_EXCEPTION_IRQ);
	return XST_SUCCESS;
}
void IntrHandler(void *CallBack,u32 Bank,u32 status){
	XGpioPs *GPIO_ptr;
	u32 read_val;
	GPIO_ptr = (XGpioPs *)CallBack;
	if(XGpioPs_ReadPin(GPIO_ptr,BTN1) == 1)
	{
		XGpioPs_WritePin(GPIO_ptr,LED0,1);
		XGpioPs_WritePin(GPIO_ptr,LED1,1);
		printf("%d\n",XGpioPs_ReadPin(&GpioPs,BTN1));
		usleep(1000000);
	}
}

按键控制数据采集

/*
 * helloworld.c: simple test application
 *
 * This application configures UART 16550 to baud rate 9600.
 * PS7 UART (Zynq) is not initialized by this application, since
 * bootrom/bsp configures it to baud rate 115200
 *
 * ------------------------------------------------
 * | UART TYPE   BAUD RATE                        |
 * ------------------------------------------------
 *   uartns550   9600
 *   uartlite    Configurable only in HW design
 *   ps7_uart    115200 (configured by bootrom/bsp)
 */

#include 
#include "platform.h"
#include "xil_printf.h"
#include "xgpiops.h"
#include "xiicps.h"
#include "xparameters.h"
#include "xscugic.h"

#define GPIO_ID XPAR_PS7_GPIO_0_DEVICE_ID
#define SCUGIC_0_ID XPAR_PS7_SCUGIC_0_DEVICE_ID
#define I2C_0_DEVICE_ID XPAR_PS7_I2C_0_DEVICE_ID
#define I2C_0_CLK 100000
#define IIC_0_SALV_ADDR 0x23 //定义器件在IIC总线中的从地址,根据ALT  ADDRESS地址引脚不同修改
                              //ALT  ADDRESS引脚接地时地址为0x23
#define GPIO_INTR_ID 52
#define SW_BANK_ID 2
#define LED0 54
#define LED1 55
#define BTN1 56
//声明结构体
static XGpioPs GpioPs;
static XGpioPs_Config *XGpioPs_Cfg;
static XScuGic GicPs;
static XScuGic_Config *XScuGic_Cfg;
// XIicPs* iicps;
static XIicPs iicps;
static XIicPs_Config * iicpscfgtr;
int status;
	double out=0;
	unsigned short tmp;
    unsignedchar Cmdon = 0x01;
	unsignedchar Cmdlight = 0x10;
	char temp[2];
int initGpio();
int setupinterrupt();
//初始化 iic
int InitIic(XIicPs *iips,XIicPs_Config *iiccfg);
void IntrHandler(void *CallBack,u32 Bank,u32 status);
int main()
{

	init_platform();
    initGpio();
    setupinterrupt();
    status=InitIic(&iicps,iicpscfgtr);
	if(status !=XST_SUCCESS){
		return XST_FAILURE;
	}
	//初始化
	status = XIicPs_MasterSendPolled(&iicps,&Cmdon,1,IIC_0_SALV_ADDR);
	if(status !=XST_SUCCESS){
		return XST_FAILURE;
	}
    usleep(10000);//延时10ms
    printf("init iic successful!\n");
    while(1)
    {
    	XGpioPs_WritePin(&GpioPs,LED0,0);
    	XGpioPs_WritePin(&GpioPs,LED1,0);

    	usleep(1000);

    }
    cleanup_platform();
    return0;
}
int initGpio(){
	int status;
	XGpioPs_Cfg = XGpioPs_LookupConfig(GPIO_ID);
	status = XGpioPs_CfgInitialize(&GpioPs,XGpioPs_Cfg,XGpioPs_Cfg->BaseAddr);
	if( status != XST_SUCCESS){
		return XST_FAILURE;
	}
	XGpioPs_SetDirectionPin(&GpioPs,LED0,0x01);
	XGpioPs_SetOutputEnablePin(&GpioPs,LED0,0x01);
	XGpioPs_SetDirectionPin(&GpioPs,LED1,0x01);
	XGpioPs_SetOutputEnablePin(&GpioPs,LED1,0x01);
	XGpioPs_SetDirectionPin(&GpioPs,BTN1,0x00);
	XGpioPs_SetOutputEnablePin(&GpioPs,BTN1,0x00);
}

int InitIic(XIicPs *iips,XIicPs_Config * iiccfg){
	int status;
	iiccfg = XIicPs_LookupConfig(I2C_0_DEVICE_ID);
	status = XIicPs_CfgInitialize(iips,iiccfg,iiccfg->BaseAddress);
	if(status !=XST_SUCCESS){
		return XST_FAILURE;
	}
	status = XIicPs_SelfTest(iips);
			if (status != XST_SUCCESS) {
				return XST_FAILURE;
			}
	status = XIicPs_SetSClk(iips,I2C_0_CLK);
	if(status !=XST_SUCCESS){
		return XST_FAILURE;
	}
	return0;
}
int setupinterrupt(){
	int status;
	//初始化异常处理
	Xil_ExceptionInit();
	//初始化中断控制器
	XScuGic_Cfg = XScuGic_LookupConfig(SCUGIC_0_ID);
	status = XScuGic_CfgInitialize(&GicPs,XScuGic_Cfg,XScuGic_Cfg->CpuBaseAddress);
	if( status != XST_SUCCESS){
			return XST_FAILURE;
	}
	//CPU中断异常注册
	Xil_ExceptionRegisterHandler(XIL_EXCEPTION_ID_INT,(Xil_ExceptionHandler)XScuGic_InterruptHandler,&GicPs);
	//链接中断信号
	status = XScuGic_Connect(&GicPs,GPIO_INTR_ID,(Xil_InterruptHandler)XGpioPs_IntrHandler,&GpioPs);
	if( status != XST_SUCCESS){
				return XST_FAILURE;
	}
	//中断类型设置
	XGpioPs_SetIntrType(&GpioPs,SW_BANK_ID,0xffffffff,0xffffffff,0x00);
	//设置中断回调函数
	XGpioPs_SetCallbackHandler(&GpioPs,(void *) &GpioPs, IntrHandler);
	//打开gpio中断
	XGpioPs_IntrEnable(&GpioPs,SW_BANK_ID,1<<(BTN1-54));
	XScuGic_Enable(&GicPs,GPIO_INTR_ID);
	Xil_ExceptionEnableMask(XIL_EXCEPTION_IRQ);
	return XST_SUCCESS;
}
void IntrHandler(void *CallBack,u32 Bank,u32 status){
	XGpioPs *GPIO_ptr;
	u32 read_val;
	GPIO_ptr = (XGpioPs *)CallBack;
	if(XGpioPs_ReadPin(GPIO_ptr,BTN1) == 1)
	{
				XGpioPs_WritePin(&GpioPs,LED0,1);
				status = XIicPs_MasterSendPolled(&iicps,&Cmdon,1,IIC_0_SALV_ADDR);
			    if(status !=XST_SUCCESS){
				   return XST_FAILURE;
			    }
				status = XIicPs_MasterSendPolled(&iicps,&Cmdlight,1,IIC_0_SALV_ADDR);
				if(status !=XST_SUCCESS){
							return XST_FAILURE;
			    }
				usleep(180000);//延时180ms
				status = XIicPs_MasterRecvPolled(&iicps,&temp,2,IIC_0_SALV_ADDR);

				//串口检测结果
				tmp = (temp[0]<<8)| temp[1];
				out = tmp/1.2;
				printf("light intensity : %.1f lx\n",out);
				usleep(1000000);
	}
}

ZYNQ-实现GPIO的中断控制