我有一个非常奇怪的不一致.
我准备读取Arduino上的二进制文件(对于midi播放器,如果你感兴趣的话).如果我尝试将Arduino上的4个字节组合成一个long,它会给我一个错误的结果.
但是,如果我在PC上使用等效代码,我会得到正确的值.
输入为:0x12481248(0x12,0x48,0x12,0x48)(实际上是一个随机数).
Arduino给出:4680.
Code :: Blocks给出:306713160.
4680与0x1248相同,是在Arduino上使用int而不是long时得到的结果(省略2个字节).
Arduino代码:
void setup(){
Serial.begin(57600);
char read1 = 0x12;
char read2 = 0x48;
char read3 = 0x12;
char read4 = 0x48;
unsigned long testint = read1<<24|read2<<16|read3<<8|read4;
unsigned long testint2 = 306713160;
Serial.println(testint);
Serial.println(testint2);
}
void loop(){}
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testint2表明它不是由Serial.println()引起的.串行监视器输出确实是:
4680
306713160
C++代码:
#include <iostream>
using namespace std;
int main(){
char read1 = 0x12;
char read2 = 0x48;
char read3 = 0x12;
char read4 = 0x48;
unsigned long testint = read1<<24|read2<<16|read3<<8|read4;
cout << testint;
} …
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