如果缓冲区包含按照以下代码存储到它的函数值，我如何将缓冲区压入堆栈？

Question

struct dev *address - 它从寄存器结构中读取地址。
unsigned int bytes- 从寄存器地址读取的数据字节数。
例如 - (0x2, 1)。 0x2 - 寄存器地址和 1 - 字节数。

i2c_read(struct dev *address, unsigned int bytes)
{
 char buff[256];
    char *p1 = buff; // Contains a pointer to a buffer of 256 bytes

 p1 = func(address, bytes); //values to be stored to the "pointer of a buffer of 256 bytes".
}

缓冲区包含要从 func(address, bytes) 存储的值。

int push() //to push the buffer into  the stack.
{
//push the buffer to stack  here?.
}

我试过这样做 -

void push(unsigned int *result_buffer)
{
    unsigned int *tos, *p1, arr_stack[MAX_SIZE];
    //MAX_SIZE is the size of the stack.
    tos = arr_stack; /* tos points to the top of stack */
    p1 = arr_stack; /* initialize p1 */
    printf("\n Simple Stack Example - Pointers");
    if (p1 == (tos + MAX_SIZE)) {
        printf("\nStatus : Stack Overflow.\n");
    } else {
        *p1 = *result_buffer;
        printf("\nPush Value : %d ", *(p1));
        p1++;
    }
}

Answer 1

你的错误在 func() 的定义中。你需要定义你的功能。假设您有一个 i2c 端口。与其通信的函数应该需要以下内容来完成它的任务：

i2c 设备的地址。
响应中预期的字节数。
用于存储响应的缓冲区地址。

最好return一个表示操作状态的代码，成功了吗？为什么失败了？

函数的签名应该是，假设错误代码表示为整数：

int i2c_read(struct dev *address, int result_length, unsigned char* result_buffer);

在调用点，您必须创建一个足够大的缓冲区来存储结果。

如：

// Example: You've just sent read serial command... to read 4 bytes serial #...

unsigned char buffer[4];

if (i2c_read(address, 4, buffer) < 0)  // buffer decays to a pointer when
                                       // passed to the function.
{
    printf("error! failed to read serial # !!!\n");
}
else
{
    printf("serial # is: %02x%02x-%02x%02x\n", buffer[0], buffer[1], buffer[2], buffer[3]); 
}

你的问题不是很清楚....

通常I2c需要发送命令和接收响应。在我见过的大多数 i2c API 中，send/receive 函数的签名是：

int i2c_sendCcommand(WORD addr, int nbytesCommand, const unsigned char* command, int nBytesResponse, unsigned char* response);

// usage:

unsigned char cmdBuffer[] = { 0x43, 0x01 };
unsigned char respBuffer[4];

if (i2c_sendCcommand(0x1234, 2, cmdBuffer, 4, respBuffer) < 0)
{
    printf("error! failed to read serial # !!!\n");
}
else
{
    printf("serial # is: %02x%02x-%02x%02x\n", respBuffer[0], 
                  respBuffer[1], respBuffer[2], respBuffer[3]); 
}

如果缓冲区包含按照以下代码存储到它的函数值，我如何将缓冲区压入堆栈？

How can I push buffer into the stack provided the buffer contains a function value stored to it as per the following code?

c

embedded

i2c

master-slave

eeprom