zynq7000ov5640图像采集代码

以下是一个简单的Zynq-7000 OV5640图像采集的代码示例：

#include "xil_printf.h"
#include "xparameters.h"
#include "xiicps.h"
#include "xgpio.h"
#include "xscugic.h"
#include "xil_exception.h"
#include "xaxidma.h"
#include "xtime_l.h"

#define CAMERA_ADDR 0x78
#define IIC_DEVICE_ID XPAR_XIICPS_0_DEVICE_ID
#define GPIO_DEVICE_ID XPAR_XGPIOPS_0_DEVICE_ID
#define DMA_DEV_ID XPAR_AXIDMA_0_DEVICE_ID
#define INTC_DEVICE_ID XPAR_SCUGIC_SINGLE_DEVICE_ID
#define INTC_GPIO_INTERRUPT_ID XPAR_XGPIOPS_0_INTR

#define WIDTH 640
#define HEIGHT 480
#define FRAME_SIZE WIDTH*HEIGHT*2 // 2 bytes per pixel

XIicPs Iic;
XGpio Gpio;
XScuGic Intc;
XAxiDma Dma;

u8 CameraConfig[][2] =
{
    {0x3a, 0x04},
    {0x67, 0xC0},
    {0x68, 0x80},
    {0x14, 0x38},
    {0x24, 0x3c},
    {0x25, 0x36},
    {0x26, 0x72},
    {0x27, 0x08},
    {0x6b, 0x4a},
    {0x13, 0xe0},
    {0x01, 0x80},
    {0x02, 0x80},
    {0x11, 0x80},
    {0x3d, 0x0f},
    {0x5a, 0x57},
    {0x5b, 0x3d},
    {0x5c, 0x11},
    {0xd3, 0x04},
    {0xe0, 0x00},
    {0xff, 0xff}
};

u16 FrameBuffer[FRAME_SIZE]; // Buffer to hold a single frame

void CameraInit()
{
    int i;
    u8 RegValue;

    XIicPs_Config *Config = XIicPs_LookupConfig(IIC_DEVICE_ID);
    XIicPs_CfgInitialize(&Iic, Config, Config->BaseAddress);
    XIicPs_Reset(&Iic);

    XGpio_Initialize(&Gpio, GPIO_DEVICE_ID);
    XGpio_SetDataDirection(&Gpio, 1, 0xffffffff);
    XGpio_DiscreteWrite(&Gpio, 1, 0);

    for (i = 0; CameraConfig[i][0] != 0xff; i++)
    {
        XIicPs_MasterSendPolled(&Iic, CameraConfig[i], 2, CAMERA_ADDR);
        while (XIicPs_BusIsBusy(&Iic));
    }

    RegValue = XGpio_DiscreteRead(&Gpio, 1);
    RegValue |= 0x01;
    XGpio_DiscreteWrite(&Gpio, 1, RegValue);
}

void DmaConfig()
{
    XAxiDma_Config *Config = XAxiDma_LookupConfig(DMA_DEV_ID);
    XAxiDma_CfgInitialize(&Dma, Config);
    XAxiDma_Reset(&Dma);
    while (!XAxiDma_ResetIsDone(&Dma));

    XAxiDma_IntrDisable(&Dma, XAXIDMA_IRQ_ALL_MASK, XAXIDMA_DEVICE_TO_DMA);
    XAxiDma_IntrDisable(&Dma, XAXIDMA_IRQ_ALL_MASK, XAXIDMA_DMA_TO_DEVICE);

    XAxiDma_SetupInterruptSystem(&Dma, INTC_DEVICE_ID, XAXIDMA_DEVICE_TO_DMA);
}

void StartDma()
{
    XAxiDma_SimpleTransfer(&Dma, (u32)FrameBuffer, FRAME_SIZE, XAXIDMA_DEVICE_TO_DMA);
}

void SetupInterrupt()
{
    XScuGic_Config *Config = XScuGic_LookupConfig(INTC_DEVICE_ID);
    XScuGic_CfgInitialize(&Intc, Config, Config->CpuBaseAddress);
    Xil_ExceptionRegisterHandler(XIL_EXCEPTION_ID_IRQ_INT, (Xil_ExceptionHandler)XScuGic_InterruptHandler, &Intc);
    Xil_ExceptionEnable();

    XScuGic_Connect(&Intc, INTC_GPIO_INTERRUPT_ID, (Xil_ExceptionHandler)StartDma, NULL);
    XScuGic_Enable(&Intc, INTC_GPIO_INTERRUPT_ID);

    XGpio_InterruptEnable(&Gpio, XGPIO_IR_CH1_MASK);
    XGpio_InterruptGlobalEnable(&Gpio);
}

int main()
{
    XTime tStart, tEnd;

    Xil_ICacheEnable();
    Xil_DCacheEnable();

    DmaConfig();
    CameraInit();
    SetupInterrupt();

    XTime_GetTime(&tStart);
    while (1)
    {
        // Wait for interrupt
    }
    XTime_GetTime(&tEnd);

    xil_printf("Frame captured in %llu clock cycles.\n", 2*(tEnd - tStart));

    Xil_DCacheDisable();
    Xil_ICacheDisable();

    return 0;
}

该代码使用了Zynq-7000的I2C和DMA模块，以及一个GPIO来触发DMA传输。在本例中，OV5640摄像头的I2C地址为0x78，使用了一组配置寄存器来设置摄像头的参数。DMA用于将帧缓冲区中的数据传输到内存中。当GPIO触发时，DMA传输开始，将采集到的数据存储在FrameBuffer数组中。