const int pingPin = 7;
const int ledPin = 11;
const int ledPin2 = 10;
int ledLevel = 0;
int ledLevel2 = 255;
int constraint = 0;
void setup()
{
pinMode(ledPin, OUTPUT);
Serial.begin(9600);
}
void loop()
{
long duration, inches, cm;
pinMode(pingPin, OUTPUT);
digitalWrite(pingPin, LOW);
delayMicroseconds(2);
digitalWrite(pingPin, HIGH);
delayMicroseconds(5);
pinMode(pingPin, INPUT);
duration = pulseIn(pingPin, HIGH);
constraint = constrain(duration, 500, 8000);
ledLevel = map(constraint, 500, 8000, 255, 0);
if (ledLevel < 192) {
analogWrite(ledPin, ledLevel);
ledLevel2 = ledLevel2 - 255;
} else if (ledlevel >= 192) {
analogWrite(ledPin, ledLevel);
analogWrite(ledPin2, ledLevel2);
}
Serial.println(duration);
delay(100);
}
这是我的arduino的代码,当有人开始向超声波传感器走去时,当有人开启第二个LED时,它会接通3/4。当我尝试编译它时,出现“'ledLevel'未在此范围内声明,”并突出显示else if语句。
答案 0 :(得分:5)
else if (ledlevel >= 192)
ledLevel而不是ledlevel(L是大写)
它应该是
else if (ledLevel >= 192)