Atmel Studio：返回包含数组的寄存器

Question

我正在 Atmel Studio 中为 Arduino 编写一个项目。在我的代码中，我有两个如下所示的函数：

unsigned char* USART_Receive(void){
    while(!(UCSR0A & (1<<RXC0)) );
    return UDR0;
}

void Transmit(){
        unsigned char *a = USART_Receive();

        unsigned char pckaffe[4] = { 0x0C, 0x0A, 0x0F, 0x0E };
        unsigned char pcpersienner[4] = { 0x0B, 0x0B, 0x0B, 0x0B }; 

        if(a == pckaffe && zeroCrossCounter() == 1){
            sendBurst();
        }
}

如果一切正常，UDR0 寄存器应该包含一个有 4 个索引的数组 (array[4])，因此对于 return 寄存器中的数组，我使用了指针。但是，我在 return UDR0 处收到以下错误：

Error invalid conversion from 'uint8_t {aka unsigned char}' to 'unsigned char*' [-fpermissive]

编辑：

亚当·斯蒂芬尼克：

uint8_t varrr = 0;

unsigned char* USART_Receive(void){
    while(!(UCSR0A & (1<<RXC0)) );
    varrr = UDR0;
    return &varrr;
}

Answer 1

断章取意地说它修复了你的整个代码，但如果你愿意的话：

#include <cstdint>

uint8_t varaible = 0;

unsigned char* USART_Receive(void){
    return varaible;
}

void Transmit(){
        unsigned char *a = USART_Receive();
}

int main(){
    Transmit();
}

将会得到：

In function 'unsigned char* USART_Receive()':
6:12: error: invalid conversion from 'uint8_t {aka unsigned char}' to 'unsigned char*' [-fpermissive]
 In function 'void Transmit()':
10:24: warning: unused variable 'a' [-Wunused-variable]

要解决此问题，只需 return 变量地址：

#include <cstdint>

uint8_t varaible = 0;

unsigned char* USART_Receive(void){
    return &varaible;
}

void Transmit(){
        unsigned char *a = USART_Receive();
}

int main(){
    Transmit();
}

Atmel Studio：返回包含数组的寄存器

Atmel Studio: Returning a register which contains an array

c++

arrays

pointers

return

atmelstudio

编辑：