GPIO程序在PC上的模拟学习

#include <stdio.h>
#include <malloc.h>
#include <memory.h>

typedef struct gpio
{
    int pr;
    int pl;
}* GPIO_MemMapPtr;

//注释为了避免内存出错
//GPIO_MemMapPtr GPIO_Ptr;    //定义一个结构体指针变量，GCC会分配一个内存的。

#define PTA_BASE_PTR ((GPIO_MemMapPtr)0x0028ff10)
#define PTD_BASE_PTR ((struct gpio*)0x0028ff50)

#define GPIO_PR_REG(base) ((base)->pr)
#define GPIO_PL_REG(base) ((base)->pl)

typedef struct
{
    int io_da;
    int io_db;
}GPIO_TypeDef;
#define GPIOB ((GPIO_TypeDef*)(0x0028ff30))

int main(int argc, char* argv[])
{
    int i = ;
    //0x0028ff10开始的8各字节内存的内容清零
    memset((int *)(0x0028ff10), , );

    GPIO_PR_REG(PTA_BASE_PTR) = 0x02;
    GPIO_PL_REG(PTA_BASE_PTR) = 0x02;

    GPIO_PR_REG(PTD_BASE_PTR) = 0x05;
    GPIO_PL_REG(PTD_BASE_PTR) = 0x06;

    //注释为了避免内存出错
    //GPIO_Ptr->pl = 0x03;
    //GPIO_Ptr->pr = 0x04;

    //下面的语句是错误的，因为GPIO_MemMapPtr GPIO_Ptr;已经被GCC分配了一个内存，
    //因此该宏定义#define PTC_BASE_PTR ((GPIO_Ptr)0x0028ff20)是错误的，不成立的。
    //GPIO_PR_REG(PTC_BASE_PTR) = 0x03;
    //GPIO_PL_REG(PTC_BASE_PTR) = 0x04;

    GPIOB->io_da = 0x01;
    GPIOB->io_db = 0x01;

    printf("data in ram 0x0028ff10 = %d\n", (int)(*(int *)(0x0028ff10)));
    printf("data in ram 0x0028ff30 = %d\n", (int)(*(int *)(0x0028ff30)));
    printf("data in ram 0x0028ff14 = %d\n", (int)(*(int *)(0x0028ff14)));
    printf("data in ram 0x0028ff34 = %d\n", (int)(*(int *)(0x0028ff34)));
    printf("data in ram 0x0028ff50 = %d\n", (int)(*(int *)(0x0028ff50)));
    printf("data in ram 0x0028ff54 = %d\n", (int)(*(int *)(0x0028ff54)));

    return ;
}

运行结果：

data in ram 0x0028ff10 = 2
data in ram 0x0028ff30 = 1
data in ram 0x0028ff14 = 2
data in ram 0x0028ff34 = 1
data in ram 0x0028ff50 = 5
data in ram 0x0028ff54 = 6

gdb的内存查看为：

预编译后gcc -E typedef_st.c -o typedef_st.i：

typedef struct gpio
{
 int pr;
 int pl;
}* GPIO_MemMapPtr;

GPIO_MemMapPtr GPIO_Ptr;
#  "typedef_st.c"
typedef struct
{
 int io_da;
 int io_db;
}GPIO_TypeDef;

int main(int argc, char* argv[])
{
 int i = ;

 memset((int *)(0x0028ff10), , );

 ((((GPIO_MemMapPtr)0x0028ff10))->pr) = 0x02;
 ((((GPIO_MemMapPtr)0x0028ff10))->pl) = 0x02;

 ((((struct gpio*)0x0028ff20))->pr) = 0x05;
 ((((struct gpio*)0x0028ff20))->pl) = 0x06;

 GPIO_Ptr->pl = 0x03;
 GPIO_Ptr->pr = 0x04;

 ((GPIO_TypeDef*)(0x0028ff30))->io_da = 0x01;
 ((GPIO_TypeDef*)(0x0028ff30))->io_db = 0x01;

 printf("data in ram 0x0028ff10 = %d\n", (int)(*(int *)(0x0028ff10)));
 printf("data in ram 0x0028ff30 = %d\n", (int)(*(int *)(0x0028ff30)));
 printf("data in ram 0x0028ff14 = %d\n", (int)(*(int *)(0x0028ff14)));
 printf("data in ram 0x0028ff34 = %d\n", (int)(*(int *)(0x0028ff34)));

    return ;
}