4 - AXI GPIO按键控制LED实验

1 实验任务

本实验任务是通过调用PL端AXI GPIO IP核，使用中断机制，实现PL端按键控制 PS端LED的功能。

2 系统框图

3 软件设计

注意事项：

1. AXI GPIO IP核是双沿触发中断，不可设置；
2. AXI GPIO IP核的中断使能和中断状态都是以通道为单位。

/***************************** Include Files ********************************/
#include <stdio.h>
#include "xil_exception.h"
#include "xparameters.h"
#include "xgpiops.h"
#include "xgpio.h"
#include "xscugic.h"
#include "xstatus.h"
#include "sleep.h"
/************************** Constant Definitions ****************************/
#define PSGPIO_DEVICE_ID  		XPAR_XGPIOPS_0_DEVICE_ID
#define AXIGPIO_DEVICE_ID		XPAR_GPIO_0_DEVICE_ID
#define INTC_DEVICE_ID			XPAR_SCUGIC_SINGLE_DEVICE_ID#define AXIGPIO_INTR_ID	    	XPAR_FABRIC_AXI_GPIO_0_IP2INTC_IRPT_INTR#define PS_LED0_GPIO_PIN		0
#define AXIGPIO_CHANNEL1		0x1
/**************************** Type Definitions ******************************//***************** Macros (Inline Functions) Definitions ********************//************************** Function Prototypes *****************************/
int  PsGpioInit(XGpioPs* PsGpioInstPtr);
int  AxiGpioInit(XGpio* AxiGpioInstPtr);
int  SetupIntrSystem(XScuGic* IntcInstPtr, XGpio* AxiGpioInstPtr, u16 AxiGpioIntrId);
void AxiGpioIntrHandler(void *CallBackRef);
/************************** Variable Definitions ****************************/
XGpioPs PsGpioInst;
XGpio   AxiGpioInst;
XScuGic IntcInst;u32 KeyPress = 0;
/****************************************************************************/int PsGpioInit(XGpioPs* PsGpioInstPtr)
{//int Status;XGpioPs_Config* PsGpioConfigPtr;//PsGpioConfigPtr = XGpioPs_LookupConfig(PSGPIO_DEVICE_ID);Status = XGpioPs_CfgInitialize(PsGpioInstPtr, PsGpioConfigPtr, PsGpioConfigPtr->BaseAddr);if (Status != XST_SUCCESS) {return XST_FAILURE;}// 设置输出XGpioPs_SetDirectionPin(PsGpioInstPtr, PS_LED0_GPIO_PIN, 1);// 使能输出XGpioPs_SetOutputEnablePin(PsGpioInstPtr, PS_LED0_GPIO_PIN, 1);//return XST_SUCCESS;
}int  AxiGpioInit(XGpio* AxiGpioInstPtr)
{//int Status;XGpio_Config* AxiGpioConfigPtr;//AxiGpioConfigPtr = XGpio_LookupConfig(AXIGPIO_DEVICE_ID);Status = XGpio_CfgInitialize(AxiGpioInstPtr, AxiGpioConfigPtr, AxiGpioConfigPtr->BaseAddress);if (Status != XST_SUCCESS) {return XST_FAILURE;}// 设置输入XGpio_SetDataDirection(AxiGpioInstPtr, AXIGPIO_CHANNEL1, 0x1);// 使能中断XGpio_InterruptEnable(AxiGpioInstPtr, XGPIO_IR_CH1_MASK);XGpio_InterruptGlobalEnable(AxiGpioInstPtr);//return XST_SUCCESS;
}/** 如何设置AXI GPIO引脚方向** XGpio gpio_instance;* int channel = 1; // 假设使用通道1* int bit_to_change = 3; // 假设要修改第3位** // 初始化GPIO* XGpio_Initialize(&gpio_instance, XPAR_XGPIOPS_0_DEVICE_ID);** // 读取当前方向寄存器的值* u32 current_direction = XGpio_GetDataDirection(&gpio_instance, channel);*
// 将第3位设置为输出（0）* u32 new_direction_output = current_direction & ~(1 << bit_to_change);* XGpio_SetDataDirection(&gpio_instance, channel, new_direction_output);** // 将第3位设置为输入（1）* u32 new_direction_input = current_direction | (1 << bit_to_change);* XGpio_SetDataDirection(&gpio_instance, channel, new_direction_input);**/int  SetupIntrSystem(XScuGic* IntcInstPtr, XGpio* AxiGpioInstPtr, u16 AxiGpioIntrId)
{//int Status;XScuGic_Config* IntcConfigPtr;// step1. 初始化中断控制器GICIntcConfigPtr= XScuGic_LookupConfig(INTC_DEVICE_ID);if (NULL == IntcConfigPtr) {return XST_FAILURE;}Status = XScuGic_CfgInitialize(IntcInstPtr, IntcConfigPtr, IntcConfigPtr->CpuBaseAddress);if (Status != XST_SUCCESS) {return XST_FAILURE;}// step2. 在处理器中初始化异常处理功能Xil_ExceptionInit();// step3. 在处理器中为IRQ中断异常注册处理程序Xil_ExceptionRegisterHandler(XIL_EXCEPTION_ID_INT, (Xil_ExceptionHandler)XScuGic_InterruptHandler, IntcInstPtr);// step4. 在处理器中使能IRQ中断异常Xil_ExceptionEnableMask(XIL_EXCEPTION_IRQ);// step5. 在GIC中为外设注册中断处理程序// XScuGic_Connect函数将中断源(Int_Id)与中断处理程序(Handler)关联起来；当中断发生时，GIC会调用中断处理程序来处理中断Status = XScuGic_Connect(IntcInstPtr, AxiGpioIntrId, (Xil_ExceptionHandler)AxiGpioIntrHandler, (void *)AxiGpioInstPtr);if (Status != XST_SUCCESS) {return XST_FAILURE;}// step6. 在GIC中设置外设中断的优先级和触发类型XScuGic_SetPriorityTriggerType(IntcInstPtr, AxiGpioIntrId, 0xA0, 0x1);// step7. 在GIC中使能外设中断XScuGic_Enable(IntcInstPtr, AxiGpioIntrId);//return XST_SUCCESS;
}void AxiGpioIntrHandler(void *CallBackRef)
{//XGpio* AxiGpioInstPtr = (XGpio*)CallBackRef;u32 IntrStatus;//IntrStatus = XGpio_InterruptGetStatus(AxiGpioInstPtr);if (IntrStatus==1){// 禁用中断XGpio_InterruptDisable(AxiGpioInstPtr, XGPIO_IR_CH1_MASK);printf("Interrupt Detected.\n");KeyPress = 1;}//return;
}int main()
{//int Status;u32 LedValue;u32 KeyValue;//printf("AXI GPIO Interrupt Control LED Test\n");//Status = PsGpioInit(&PsGpioInst);if (Status == XST_FAILURE) {printf("PS GPIO Init Failed.\n");}//Status = AxiGpioInit(&AxiGpioInst);if (Status == XST_FAILURE) {printf("AXI GPIO Init Failed.\n");}//Status = SetupIntrSystem(&IntcInst, &AxiGpioInst, AXIGPIO_INTR_ID);if (Status == XST_FAILURE) {printf("Setup Interrupt System Failed.\n");}//while(1){if (KeyPress==1){usleep(200000);KeyValue = XGpio_DiscreteRead(&AxiGpioInst, AXIGPIO_CHANNEL1);if ((KeyValue & (1 << 0)) == 0) {LedValue = ~XGpioPs_ReadPin(&PsGpioInst, PS_LED0_GPIO_PIN);XGpioPs_WritePin(&PsGpioInst, PS_LED0_GPIO_PIN, LedValue);}KeyPress = 0;XGpio_InterruptClear(&AxiGpioInst, XGPIO_IR_CH1_MASK);XGpio_InterruptEnable(&AxiGpioInst, XGPIO_IR_CH1_MASK);}}//return 0;
}