Question

I have a problem using a macro as a function parameter.

I have this macro:

#define PD13 GPIOD, GPIO_Pin_13

GPIOD and GPIO_Pin_13 are macros too.

#define GPIO_Pin_13 ((uint16_t)0x2000)
#define GPIOD  ((GPIO_TypeDef *) GPIOD_BASE)

in which GPIOD_BASE is a memory address.

I'm using it as argument for this function:

PinType initPin(GPIO_TypeDef* GPIOx, uint16_t GPIO_Pin) {
PinType pin;
if (GPIOx == GPIOA) {
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
} else if (GPIOx == GPIOB) {
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
} else if (GPIOx == GPIOC) {
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC, ENABLE);
} else if (GPIOx == GPIOD) {
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE);
} else {
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE, ENABLE);
}
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(GPIOx, &GPIO_InitStructure);
GPIO_ResetBits(GPIOx, GPIO_Pin);
pin.GPIO_Reg = GPIOx;
pin.GPIO_Pin = GPIO_Pin;
pin.status = 1;
return pin;
}
PinType p1
p1 = initPin(PD13);

In this way everything works well, but if I try to add an argument to the initPin function, like:

void initPin(PinType *pin, GPIO_TypeDef* GPIOx, uint16_t GPIO_Pin) {
if (GPIOx == GPIOA) {
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
} else if (GPIOx == GPIOB) {
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
} else if (GPIOx == GPIOC) {
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC, ENABLE);
} else if (GPIOx == GPIOD) {
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE);
} else {
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE, ENABLE);
}
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(GPIOx, &GPIO_InitStructure);
GPIO_ResetBits(GPIOx, GPIO_Pin);
pin->GPIO_Reg = GPIOx;
pin->GPIO_Pin = GPIO_Pin;
pin->status = 1;
}

PinType p1;
initPin(&p1, PD13);

The arguments are messed up and are incorrect.

Is there any way so I can use a macro for passing a part of the arguments while the others are passed normally?

Answer 1

有没有办法让我可以使用宏来传递部分内容争论而其他人正常通过？

没有。宏扩展完全是文本的，没有机制来抑制所选参数的扩展。

但是，您可以定义不同的宏来实现类似的效果：

#define PD13_2args GPIOD, GPIO_Pin_13
#define PD13_1arg  GPIO_Pin_13
initPin(PD13_2args);
initPin(&p1, PD13_1arg);

您可能还想了解可变参数宏，这是C99及更高版本可用的功能，结合可变参数函数（例如printf）。

C Macro concatenation as function argument

1 个答案: