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Question

基本上，我正在从RTOS中的另一个线程中获取数据。这些数据是板上的一个引脚。所有IO端口都位于iofine.h文件中的结构/联合中。例如，看看Micrium是如何制作它的：

struct st_portd {
union {
    unsigned char BYTE;
    struct {
        unsigned char B0:1;
        unsigned char B1:1;
        unsigned char B2:1;
        unsigned char B3:1;
        unsigned char B4:1;
        unsigned char B5:1;
        unsigned char B6:1;
        unsigned char B7:1;
    } BIT;
} DDR;
unsigned char wk0[31];
union {
    unsigned char BYTE;
    struct {
        unsigned char B0:1;
        unsigned char B1:1;
        unsigned char B2:1;
        unsigned char B3:1;
        unsigned char B4:1;
        unsigned char B5:1;
        unsigned char B6:1;
        unsigned char B7:1;
    } BIT;
} DR;
unsigned char wk1[31];
union {
    unsigned char BYTE;
    struct {
        unsigned char B0:1;
        unsigned char B1:1;
        unsigned char B2:1;
        unsigned char B3:1;
        unsigned char B4:1;
        unsigned char B5:1;
        unsigned char B6:1;
        unsigned char B7:1;
    } BIT;
} PORT;
unsigned char wk2[31];
union {
    unsigned char BYTE;
    struct {
        unsigned char B0:1;
        unsigned char B1:1;
        unsigned char B2:1;
        unsigned char B3:1;
        unsigned char B4:1;
        unsigned char B5:1;
        unsigned char B6:1;
        unsigned char B7:1;
    } BIT;
} ICR;
unsigned char wk3[95];
union {
    unsigned char BYTE;
    struct {
        unsigned char B0:1;
        unsigned char B1:1;
        unsigned char B2:1;
        unsigned char B3:1;
        unsigned char B4:1;
        unsigned char B5:1;
        unsigned char B6:1;
        unsigned char B7:1;
    } BIT;
} PCR;
};

如果你问我的话。因此，我将这个引脚保存为结构中的2个字符，称为Port和Pin。

struct StepperMotor {
  CPU_INT32U ID;
  CPU_CHAR *EnablePort;
  CPU_CHAR EnablePin;
  CPU_CHAR *DirectionPort;
  CPU_CHAR DirectionPin;
  CPU_CHAR *PulsePort;
  CPU_CHAR PulsePin;
};

我想以这样的方式使用引脚：

(struct st_portd)(steppermotor->PulsePort)->DR.BYTE ^= (1 << steppermotor->PulsePin);

步进电机是结构。只有这样我才会说错话

请求成员“DR”的东西不是一个结构或联盟

我如何能够使用步进电机->PulsePort->DR.BYTE而不为它创建一个新的变量？我希望任何人都能帮我！

Answer 1

由于您正在转换一个指针，所以您应该将其转换为指向结构的指针，而不是结构本身，如下所示：

((struct st_portd*)steppermotor->PulsePort)->DR.BYTE ^= (1 << steppermotor->PulsePin);

还请注意，您的括号在一个错误的地方。