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Linux-ubuntu点LED灯C语言版

news 文章来源：https://blog.csdn.net/xxxx123445/article/details/144530957 2025/5/15 4:14:21

一，C语言点灯

1.寄存器配置

设置为SVC模式，复用寄存器设置GPIO1-IO003,设置电气属性，设置为输出模式。

2.软件

汇编语言对模式设置，并且将堆栈指针指向主程序：

.global _start_start:
/*设置为svr模式 */mrs r0,cpsr /*读取cpsr现在状态 */bic r0,r0,#0x1forr r0,r0,#0x13msr cpsr,r0
/*SP堆栈指针 */ldr sp,=0x80200000b main

对寄存器进行配置：

#ifndef _MAIN_H
#define _MAIN_H/*定义寄存器*/#define CCMCCGR0 *((volatile unsigned int*)0x020c4068) //打开时钟
#define CCMCCGR1 *((volatile unsigned int*)0x020c406c) //打开时钟
#define CCMCCGR2 *((volatile unsigned int*)0x020c4070) //打开时钟
#define CCMCCGR3 *((volatile unsigned int*)0x020c4074) //打开时钟
#define CCMCCGR4 *((volatile unsigned int*)0x020c4078) //打开时钟
#define CCMCCGR5 *((volatile unsigned int*)0x020c407c) //打开时钟
#define CCMCCGR6 *((volatile unsigned int*)0x020c4080) //打开时钟#define MUX_CTL_PAD *((volatile unsigned int*)0x020e0068)//复用功能
#define PAD_CTL_PAD *((volatile unsigned int*)0x020e02f4)//电器属性
#define GDIR *((volatile unsigned int*)0x0209c004)//输入输出
#define DR *((volatile unsigned int*)0x0209c000) //高低电平 #endif

主程序：

#include "main.h"
void led_clock(void)//开启外部时钟
{CCMCCGR0 = 0xffffffff;CCMCCGR1 = 0xffffffff;CCMCCGR2 = 0xffffffff;CCMCCGR3 = 0xffffffff;CCMCCGR4 = 0xffffffff;CCMCCGR5 = 0xffffffff;CCMCCGR6 = 0xffffffff;
}
void led_init(void)
{MUX_CTL_PAD = 0x5;PAD_CTL_PAD = 0x10B0;GDIR = 0x8;DR = 0x0;
}
void delay_us(volatile unsigned int n)
{while(n--){}
}
void delay_1ms(volatile unsigned int n)
{while(n--){delay_us(0x7ff);}
}
void led_on(void)
{DR &= ~(1<<3);
}
void led_off(void)
{DR |= (1<<3);
}
int main(void)
{led_clock();led_init();while(1){led_on();delay_1ms(500);led_off();delay_1ms(500);}return 0;    
}

执行，先根据编译顺序，将汇编的放在前面，将主函数放在后面，程序地址放在87800000，text程序段，先说明顺序，再说明数据段格式，最后是全局变量或者局部变量初始化但是未定义段bss，正常删除即可。

SECTIONS{. = 0X87800000;.text :{start.omain.o*(.text)}.rodata ALIGN(4) : {*(.rodata*)}.data ALIGN(4) : { *(.data) }__bss_start=.;.bss ALIGN(4) : { *(.bss) *(COMMON) }__bss_end=.;
}

Mkefile文件： $@ - 设置的目标文件比如对 main . bin :$ (objects)这部分， $@ 就是指 main . bin ，$ ^-依赖的所有文件，就是 $(o bj ec t s) ，即 s t a r t . o 和 main . o,$ <-依赖的第一个文件，start.o，如果针对%.o :%.S，就是后缀为.S的第一个文件。
对于-Wall,显示编译的过程， -nostdlib表示不依赖系统或者库的文件，防止定义的头文件和库里面一样，从而出现报错。

objects := start.o main.o
main.bin :$(objects)arm-linux-gnueabihf-ld -Timux6u.lds $^ -o main.elfarm-linux-gnueabihf-objcopy -O binary -S main.elf $@arm-linux-gnueabihf-objdump -D -m arm  main.elf > main.dis
%.o : %.sarm-linux-gnueabihf-gcc -Wall -nostdlib -c -o $@ $<
%.o : %.Sarm-linux-gnueabihf-gcc -Wall -nostdlib -c -o $@ $<
%.o : %.carm-linux-gnueabihf-gcc -Wall -nostdlib -c -o $@ $<
clean:rm -rf *.o main.bin main.elf main.dis main.imx
run:sudo ./uuu load.imx

先用：./imxdownload main.bin /dev/db,将main.bin变为mian.imx文件，再执行make run即可实现不用读卡器传输数据。这样可以生成bin文件的头文件，然后再用uuu通过USB数据线传输。

二，模仿stm32格式修改程序

针对stm32格式，主要就是修改头文件，将寄存器组用结构体来定义，然后给出寄存器组的首地址，将结构体和首地址结合起来，构成这个寄存器组。

#ifndef _IMX6U_H
#define _IMX6U_H
#define CCM_BASE                    (0x020c4000)//时钟寄存器的初地址
#define CCM_ANALOG_BASE				(0X020C8000)//暂时不用
#define IMUX_SW_MUX_BASE            (0x02e00044)//复用寄存器初始地址
#define IOMUX_SW_PAD_BASE			(0X020E0204)//电器属性
#define GPIO1_BASE                  (0x0209C000)
#define GPIO2_BASE                  (0x020A0000)
#define GPIO3_BASE                  (0x020A4000)
#define GPIO4_BASE                  (0x020A8000)
#define GPIO5_BASE                  (0x020AC000)
typedef struct
{volatile unsigned int CCR;volatile unsigned int CCDR;volatile unsigned int CSR;volatile unsigned int CCSR;volatile unsigned int CACRR;volatile unsigned int CBCDR;volatile unsigned int CBCMR;volatile unsigned int CSCMR1;volatile unsigned int CSCMR2;volatile unsigned int CSCDR1;volatile unsigned int CS1CDR;volatile unsigned int CS2CDR;volatile unsigned int CDCDR;volatile unsigned int CHSCCDR;volatile unsigned int CSCDR2;volatile unsigned int CSCDR3;	volatile unsigned int RESERVED_1[2];volatile unsigned int CDHIPR;  volatile unsigned int RESERVED_2[2];volatile unsigned int CLPCR;volatile unsigned int CISR;volatile unsigned int CIMR;volatile unsigned int CCOSR;volatile unsigned int CGPR;volatile unsigned int CCGR0;volatile unsigned int CCGR1;volatile unsigned int CCGR2;volatile unsigned int CCGR3;volatile unsigned int CCGR4;volatile unsigned int CCGR5;volatile unsigned int CCGR6;volatile unsigned int RESERVED_3[1];volatile unsigned int CMEOR;	}CCM_Type;//时钟寄存器相关
typedef struct 
{volatile unsigned int PLL_ARM;volatile unsigned int PLL_ARM_SET;volatile unsigned int PLL_ARM_CLR;volatile unsigned int PLL_ARM_TOG;volatile unsigned int PLL_USB1;volatile unsigned int PLL_USB1_SET;volatile unsigned int PLL_USB1_CLR;volatile unsigned int PLL_USB1_TOG;volatile unsigned int PLL_USB2;volatile unsigned int PLL_USB2_SET;volatile unsigned int PLL_USB2_CLR;volatile unsigned int PLL_USB2_TOG;volatile unsigned int PLL_SYS;volatile unsigned int PLL_SYS_SET;volatile unsigned int PLL_SYS_CLR;volatile unsigned int PLL_SYS_TOG;volatile unsigned int PLL_SYS_SS;volatile unsigned int RESERVED_1[3];volatile unsigned int PLL_SYS_NUM;volatile unsigned int RESERVED_2[3];volatile unsigned int PLL_SYS_DENOM; volatile unsigned int RESERVED_3[3];volatile unsigned int PLL_AUDIO;volatile unsigned int PLL_AUDIO_SET;volatile unsigned int PLL_AUDIO_CLR;volatile unsigned int PLL_AUDIO_TOG;volatile unsigned int PLL_AUDIO_DENOM;volatile unsigned int RESERVED_4[3];volatile unsigned int PLL_VIDEO;volatile unsigned int PLL_VIDEO_SET;volatile unsigned int PLL_VIDEO_CLR;volatile unsigned int PLL_VIDEO_TOG;volatile unsigned int PLL_VIDEO_NUM;volatile unsigned int RESERVED_5[3];volatile unsigned int PLL_VIDEO_DENOM;volatile unsigned int RESERVED_6[7];volatile unsigned int PLL_ENET;volatile unsigned int PLL_ENET_SET;volatile unsigned int PLL_ENET_CLR;volatile unsigned int PLL_ENET_TOG;volatile unsigned int PFD_480;volatile unsigned int PFD_480_SET;volatile unsigned int PFD_480_CLR;volatile unsigned int PFD_480_TOG;volatile unsigned int PFD_528;volatile unsigned int PFD_528_SET;volatile unsigned int PFD_528_CLR;volatile unsigned int PFD_528_TOG;volatile unsigned int RESERVED_7[16];volatile unsigned int MISC0;volatile unsigned int MISC0_SET;volatile unsigned int MISC0_CLR;volatile unsigned int MISC0_TOG;volatile unsigned int MISC1;volatile unsigned int MISC1_SET;volatile unsigned int MISC1_CLR;volatile unsigned int MISC1_TOG;volatile unsigned int MISC2;volatile unsigned int MISC2_SET;volatile unsigned int MISC2_CLR;volatile unsigned int MISC2_TOG;
} CCM_ANALOG_Type;
typedef struct 
{volatile unsigned int BOOT_MODE0;volatile unsigned int BOOT_MODE1;volatile unsigned int SNVS_TAMPER0;volatile unsigned int SNVS_TAMPER1;volatile unsigned int SNVS_TAMPER2;volatile unsigned int SNVS_TAMPER3;volatile unsigned int SNVS_TAMPER4;volatile unsigned int SNVS_TAMPER5;volatile unsigned int SNVS_TAMPER6;volatile unsigned int SNVS_TAMPER7;volatile unsigned int SNVS_TAMPER8;volatile unsigned int SNVS_TAMPER9;volatile unsigned int JTAG_MOD;volatile unsigned int JTAG_TMS;volatile unsigned int JTAG_TDO;volatile unsigned int JTAG_TDI;volatile unsigned int JTAG_TCK;volatile unsigned int JTAG_TRST_B;volatile unsigned int GPIO1_IO00;volatile unsigned int GPIO1_IO01;volatile unsigned int GPIO1_IO02;volatile unsigned int GPIO1_IO03;volatile unsigned int GPIO1_IO04;volatile unsigned int GPIO1_IO05;volatile unsigned int GPIO1_IO06;volatile unsigned int GPIO1_IO07;volatile unsigned int GPIO1_IO08;volatile unsigned int GPIO1_IO09;volatile unsigned int UART1_TX_DATA;volatile unsigned int UART1_RX_DATA;volatile unsigned int UART1_CTS_B;volatile unsigned int UART1_RTS_B;volatile unsigned int UART2_TX_DATA;volatile unsigned int UART2_RX_DATA;volatile unsigned int UART2_CTS_B;volatile unsigned int UART2_RTS_B;volatile unsigned int UART3_TX_DATA;volatile unsigned int UART3_RX_DATA;volatile unsigned int UART3_CTS_B;volatile unsigned int UART3_RTS_B;volatile unsigned int UART4_TX_DATA;volatile unsigned int UART4_RX_DATA;volatile unsigned int UART5_TX_DATA;volatile unsigned int UART5_RX_DATA;volatile unsigned int ENET1_RX_DATA0;volatile unsigned int ENET1_RX_DATA1;volatile unsigned int ENET1_RX_EN;volatile unsigned int ENET1_TX_DATA0;volatile unsigned int ENET1_TX_DATA1;volatile unsigned int ENET1_TX_EN;volatile unsigned int ENET1_TX_CLK;volatile unsigned int ENET1_RX_ER;volatile unsigned int ENET2_RX_DATA0;volatile unsigned int ENET2_RX_DATA1;volatile unsigned int ENET2_RX_EN;volatile unsigned int ENET2_TX_DATA0;volatile unsigned int ENET2_TX_DATA1;volatile unsigned int ENET2_TX_EN;volatile unsigned int ENET2_TX_CLK;volatile unsigned int ENET2_RX_ER;volatile unsigned int LCD_CLK;volatile unsigned int LCD_ENABLE;volatile unsigned int LCD_HSYNC;volatile unsigned int LCD_VSYNC;volatile unsigned int LCD_RESET;volatile unsigned int LCD_DATA00;volatile unsigned int LCD_DATA01;volatile unsigned int LCD_DATA02;volatile unsigned int LCD_DATA03;volatile unsigned int LCD_DATA04;volatile unsigned int LCD_DATA05;volatile unsigned int LCD_DATA06;volatile unsigned int LCD_DATA07;volatile unsigned int LCD_DATA08;volatile unsigned int LCD_DATA09;volatile unsigned int LCD_DATA10;volatile unsigned int LCD_DATA11;volatile unsigned int LCD_DATA12;volatile unsigned int LCD_DATA13;volatile unsigned int LCD_DATA14;volatile unsigned int LCD_DATA15;volatile unsigned int LCD_DATA16;volatile unsigned int LCD_DATA17;volatile unsigned int LCD_DATA18;volatile unsigned int LCD_DATA19;volatile unsigned int LCD_DATA20;volatile unsigned int LCD_DATA21;volatile unsigned int LCD_DATA22;volatile unsigned int LCD_DATA23;volatile unsigned int NAND_RE_B;volatile unsigned int NAND_WE_B;volatile unsigned int NAND_DATA00;volatile unsigned int NAND_DATA01;volatile unsigned int NAND_DATA02;volatile unsigned int NAND_DATA03;volatile unsigned int NAND_DATA04;volatile unsigned int NAND_DATA05;volatile unsigned int NAND_DATA06;volatile unsigned int NAND_DATA07;volatile unsigned int NAND_ALE;volatile unsigned int NAND_WP_B;volatile unsigned int NAND_READY_B;volatile unsigned int NAND_CE0_B;volatile unsigned int NAND_CE1_B;volatile unsigned int NAND_CLE;volatile unsigned int NAND_DQS;volatile unsigned int SD1_CMD;volatile unsigned int SD1_CLK;volatile unsigned int SD1_DATA0;volatile unsigned int SD1_DATA1;volatile unsigned int SD1_DATA2;volatile unsigned int SD1_DATA3;volatile unsigned int CSI_MCLK;volatile unsigned int CSI_PIXCLK;volatile unsigned int CSI_VSYNC;volatile unsigned int CSI_HSYNC;volatile unsigned int CSI_DATA00;volatile unsigned int CSI_DATA01;volatile unsigned int CSI_DATA02;volatile unsigned int CSI_DATA03;volatile unsigned int CSI_DATA04;volatile unsigned int CSI_DATA05;volatile unsigned int CSI_DATA06;volatile unsigned int CSI_DATA07;
}IOMUX_SW_MUX_Type;
typedef struct 
{volatile unsigned int DRAM_ADDR00;volatile unsigned int DRAM_ADDR01;volatile unsigned int DRAM_ADDR02;volatile unsigned int DRAM_ADDR03;volatile unsigned int DRAM_ADDR04;volatile unsigned int DRAM_ADDR05;volatile unsigned int DRAM_ADDR06;volatile unsigned int DRAM_ADDR07;volatile unsigned int DRAM_ADDR08;volatile unsigned int DRAM_ADDR09;volatile unsigned int DRAM_ADDR10;volatile unsigned int DRAM_ADDR11;volatile unsigned int DRAM_ADDR12;volatile unsigned int DRAM_ADDR13;volatile unsigned int DRAM_ADDR14;volatile unsigned int DRAM_ADDR15;volatile unsigned int DRAM_DQM0;volatile unsigned int DRAM_DQM1;volatile unsigned int DRAM_RAS_B;volatile unsigned int DRAM_CAS_B;volatile unsigned int DRAM_CS0_B;volatile unsigned int DRAM_CS1_B;volatile unsigned int DRAM_SDWE_B;volatile unsigned int DRAM_ODT0;volatile unsigned int DRAM_ODT1;volatile unsigned int DRAM_SDBA0;volatile unsigned int DRAM_SDBA1;volatile unsigned int DRAM_SDBA2;volatile unsigned int DRAM_SDCKE0;volatile unsigned int DRAM_SDCKE1;volatile unsigned int DRAM_SDCLK0_P;volatile unsigned int DRAM_SDQS0_P;volatile unsigned int DRAM_SDQS1_P;volatile unsigned int DRAM_RESET;volatile unsigned int TEST_MODE;volatile unsigned int POR_B;volatile unsigned int ONOFF;volatile unsigned int SNVS_PMIC_ON_REQ;volatile unsigned int CCM_PMIC_STBY_REQ;volatile unsigned int BOOT_MODE0;volatile unsigned int BOOT_MODE1;volatile unsigned int SNVS_TAMPER0;volatile unsigned int SNVS_TAMPER1;volatile unsigned int SNVS_TAMPER2;volatile unsigned int SNVS_TAMPER3;volatile unsigned int SNVS_TAMPER4;volatile unsigned int SNVS_TAMPER5;volatile unsigned int SNVS_TAMPER6;volatile unsigned int SNVS_TAMPER7;volatile unsigned int SNVS_TAMPER8;volatile unsigned int SNVS_TAMPER9;volatile unsigned int JTAG_MOD;volatile unsigned int JTAG_TMS;volatile unsigned int JTAG_TDO;volatile unsigned int JTAG_TDI;volatile unsigned int JTAG_TCK;volatile unsigned int JTAG_TRST_B;volatile unsigned int GPIO1_IO00;volatile unsigned int GPIO1_IO01;volatile unsigned int GPIO1_IO02;volatile unsigned int GPIO1_IO03;volatile unsigned int GPIO1_IO04;volatile unsigned int GPIO1_IO05;volatile unsigned int GPIO1_IO06;volatile unsigned int GPIO1_IO07;volatile unsigned int GPIO1_IO08;volatile unsigned int GPIO1_IO09;volatile unsigned int UART1_TX_DATA;volatile unsigned int UART1_RX_DATA;volatile unsigned int UART1_CTS_B;volatile unsigned int UART1_RTS_B;volatile unsigned int UART2_TX_DATA;volatile unsigned int UART2_RX_DATA;volatile unsigned int UART2_CTS_B;volatile unsigned int UART2_RTS_B;volatile unsigned int UART3_TX_DATA;volatile unsigned int UART3_RX_DATA;volatile unsigned int UART3_CTS_B;volatile unsigned int UART3_RTS_B;volatile unsigned int UART4_TX_DATA;volatile unsigned int UART4_RX_DATA;volatile unsigned int UART5_TX_DATA;volatile unsigned int UART5_RX_DATA;volatile unsigned int ENET1_RX_DATA0;volatile unsigned int ENET1_RX_DATA1;volatile unsigned int ENET1_RX_EN;volatile unsigned int ENET1_TX_DATA0;volatile unsigned int ENET1_TX_DATA1;volatile unsigned int ENET1_TX_EN;volatile unsigned int ENET1_TX_CLK;volatile unsigned int ENET1_RX_ER;volatile unsigned int ENET2_RX_DATA0;volatile unsigned int ENET2_RX_DATA1;volatile unsigned int ENET2_RX_EN;volatile unsigned int ENET2_TX_DATA0;volatile unsigned int ENET2_TX_DATA1;volatile unsigned int ENET2_TX_EN;volatile unsigned int ENET2_TX_CLK;volatile unsigned int ENET2_RX_ER;volatile unsigned int LCD_CLK;volatile unsigned int LCD_ENABLE;volatile unsigned int LCD_HSYNC;volatile unsigned int LCD_VSYNC;volatile unsigned int LCD_RESET;volatile unsigned int LCD_DATA00;volatile unsigned int LCD_DATA01;volatile unsigned int LCD_DATA02;volatile unsigned int LCD_DATA03;volatile unsigned int LCD_DATA04;volatile unsigned int LCD_DATA05;volatile unsigned int LCD_DATA06;volatile unsigned int LCD_DATA07;volatile unsigned int LCD_DATA08;volatile unsigned int LCD_DATA09;volatile unsigned int LCD_DATA10;volatile unsigned int LCD_DATA11;volatile unsigned int LCD_DATA12;volatile unsigned int LCD_DATA13;volatile unsigned int LCD_DATA14;volatile unsigned int LCD_DATA15;volatile unsigned int LCD_DATA16;volatile unsigned int LCD_DATA17;volatile unsigned int LCD_DATA18;volatile unsigned int LCD_DATA19;volatile unsigned int LCD_DATA20;volatile unsigned int LCD_DATA21;volatile unsigned int LCD_DATA22;volatile unsigned int LCD_DATA23;volatile unsigned int NAND_RE_B;volatile unsigned int NAND_WE_B;volatile unsigned int NAND_DATA00;volatile unsigned int NAND_DATA01;volatile unsigned int NAND_DATA02;volatile unsigned int NAND_DATA03;volatile unsigned int NAND_DATA04;volatile unsigned int NAND_DATA05;volatile unsigned int NAND_DATA06;volatile unsigned int NAND_DATA07;volatile unsigned int NAND_ALE;volatile unsigned int NAND_WP_B;volatile unsigned int NAND_READY_B;volatile unsigned int NAND_CE0_B;volatile unsigned int NAND_CE1_B;volatile unsigned int NAND_CLE;volatile unsigned int NAND_DQS;volatile unsigned int SD1_CMD;volatile unsigned int SD1_CLK;volatile unsigned int SD1_DATA0;volatile unsigned int SD1_DATA1;volatile unsigned int SD1_DATA2;volatile unsigned int SD1_DATA3;volatile unsigned int CSI_MCLK;volatile unsigned int CSI_PIXCLK;volatile unsigned int CSI_VSYNC;volatile unsigned int CSI_HSYNC;volatile unsigned int CSI_DATA00;volatile unsigned int CSI_DATA01;volatile unsigned int CSI_DATA02;volatile unsigned int CSI_DATA03;volatile unsigned int CSI_DATA04;volatile unsigned int CSI_DATA05;volatile unsigned int CSI_DATA06;volatile unsigned int CSI_DATA07;volatile unsigned int GRP_ADDDS;volatile unsigned int GRP_DDRMODE_CTL;volatile unsigned int GRP_B0DS;volatile unsigned int GRP_DDRPK;volatile unsigned int GRP_CTLDS;volatile unsigned int GRP_B1DS;volatile unsigned int GRP_DDRHYS;volatile unsigned int GRP_DDRPKE;volatile unsigned int GRP_DDRMODE;volatile unsigned int GRP_DDR_TYPE;
}IOMUX_SW_PAD_Type;typedef struct 
{volatile unsigned int DR;							volatile unsigned int GDIR; 							volatile unsigned int PSR;								volatile unsigned int ICR1; 							volatile unsigned int ICR2; 							 volatile unsigned int IMR;								 volatile unsigned int ISR;			volatile unsigned int EDGE_SEL;  
}GPIO_Type;#define CCM ((CCM_Type *)CCM_BASE)
#define CCM_ANALOG ((CCM_ANALOG_Type *)CCM_ANALOG_BASE)
#define IOMUX_SW_MUX ((IOMUX_SW_MUX_Type *)IMUX_SW_MUX_BASE)
#define IOMUX_SW_PAD ((IOMUX_SW_PAD_Type *)IOMUX_SW_PAD_BASE)
#define GPIO1 ((GPIO_Type *)GPIO1_BASE)
#define GPIO2 ((GPIO_Type *)GPIO2_BASE)
#endif

比如：#define CCM_BASE (0x020c4000)//时钟寄存器的初地址
#define CCM ((CCM_Type )CCM_BASE)，将首地址CCM_BASE定义为CCM_Type 结构体类型指针（强制类型转换），然后宏定义为CCM，调用其中的寄存器比如CCM->CCGR0。通常用于将一个特定的内存地址（这里是 CCM_BASE）映射为一个指向特定结构体类型（CCM_Type）的指针。(CCM_Type)：这是一个类型转换操作，将 CCM_BASE 的值（通常是一个内存地址常量，比如十六进制表示的某个地址）强制转换为指向 CCM_Type 结构体类型的指针。意味着后续可以像访问结构体成员那样去访问和操作对应的硬件资源了。

三，镜像头文件和板子读写程序方式

1.启动方式

通过BOOT_MODE1和BOOT_MODE0决定启动方式，对应拨码开关1和2：
在这里插入图片描述
串行下载：连接OTG接口，通过 USB口向开发板上的 SD/EMMC、NAND 等存储设备下载代码。
内部BOOT模式：，芯片会执行内部的 boot ROM 代码，这段 boot ROM 代码会进行硬件初始化(一部分外设)，然后从 boot 设备(就是存放代码的设备、比如 SD/EMMC、NAND)中将代码拷贝出来复制到指定的 RAM 中，一般是 DDR。

2.镜像的头文件

main.imx和main.bin文件的区别就是main.imx比bin多了头文件，头文件包①IVT②BOOT DATA③DCD，大小为4kbyte，其中3kbyte为①②③，1kbyte的偏移地址。最终烧写到 I.MX6U 中的程序其组成为：IVT+Boot data+DCD+.bin。内部 Boot ROM 会将 main.imx 拷贝到 DDR 中,main.imx 在 DDR 中的起始地址就是 0X87800000-
3072=0X877FF400。