模仿stm32开发I.MX6U
Posted 等不到星光等时光呀
tags:
篇首语：本文由小常识网(cha138.com)小编为大家整理，主要介绍了模仿stm32开发I.MX6U相关的知识，希望对你有一定的参考价值。
模仿stm32开发I.MX6U
硬件所使用的是正点原子的I.MX6U-ALPHA开发板
我们在学习 STM32 的时候，可以使用“GPIOB->ODR”这种方式来给GPIOB 的寄存器 ODR 赋值，因为在 STM32 中同属于一个外设的所有寄存器地址基本是相邻的(有些会有保留寄存器)。因此我们可以借助 C 语言里面的结构体成员地址递增的特点来将某个外设的所有寄存器写入到一个结构体里面，然后定义一个结构体指针指向这个外设的寄存器基地址，这样我们就可以通过这个结构体指针来访问这个外设的所有寄存器。同理，I.MX6U 也可以使用这种方法来定义外设寄存器。
一、代码实现
创建 VSCode 工程，工作区名字为“ledc_stm32”，新建三个文件：start.S、main.c 和 imx6ul.h
1、汇编程序的编写
在start.s中写入以下代码：
.global _start /* 全局标号 */
/*
* 描述： _start函数，程序从此函数开始执行，此函数主要功能是设置C
* 运行环境。
*/
_start:
/* 进入SVC模式 */
mrs r0, cpsr
bic r0, r0, #0x1f /* 将r0寄存器中的低5位清零，也就是cpsr的M0~M4 */
orr r0, r0, #0x13 /* r0或上0x13,表示使用SVC模式 */
msr cpsr, r0 /* 将r0 的数据写入到cpsr_c中 */
ldr sp,=0X80200000 /* 设置栈指针 */
b main /* 跳转到main函数 */
2、C 语言部分实验程序编写
在imx6ul.h中写入如下代码：
/*
* 外设寄存器组的基地址
*/
#define CCM_BASE (0X020C4000)
#define CCM_ANALOG_BASE (0X020C8000)
#define IOMUX_SW_MUX_BASE (0X020E0014)
#define IOMUX_SW_PAD_BASE (0X020E0204)
#define GPIO1_BASE (0x0209C000)
#define GPIO2_BASE (0x020A0000)
#define GPIO3_BASE (0x020A4000)
#define GPIO4_BASE (0x020A8000)
#define GPIO5_BASE (0x020AC000)
/*
* CCM寄存器结构体定义，分为CCM和CCM_ANALOG
*/
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;
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;
/*
* IOMUX寄存器组
*/
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;
以上是关于模仿stm32开发I.MX6U的主要内容，如果未能解决你的问题，请参考以下文章