PIR传感器不工作的原因？

我有一个带有 HC-SR501 PIR 的 ESP8266，我已经将其解析到电路板上以进行 3.3v 操作。
当我在上面运行一个非常简单的代码时，它运行得很好。
使用相同的接线设置，以及与之前使用温度传感器的更大程序的一部分相同的代码，它似乎总是在继续阅读？
这是简单的代码和输出。它检测到动作并立即启动。
代码：全选int ledPin = 13;                // choose the pin for the LED
int inputPin = 4;               // choose the input pin (for PIR sensor)
int pirState = LOW;             // we start, assuming no motion detected
int val = 0;                    // variable for reading the pin status

void setup() {
  pinMode(ledPin, OUTPUT);      // declare LED as output
  pinMode(inputPin, INPUT);     // declare sensor as input
  Serial.begin(115200);
  Serial.println(\"Starting up\");
}

void loop(){
  val = digitalRead(inputPin);  // read input value
  Serial.println((String)\"the value of val is \" +val);
  if (val == HIGH)  // check if the input is HIGH
  {            
    Serial.println(\"Motion is on\");
  
    if (pirState == LOW)
  {
      Serial.println(\"Motion detected!\"); // print on output change
      pirState = HIGH;
    }
  }
  else
  {
    digitalWrite(ledPin, LOW); // turn LED OFF
  
    if (pirState == HIGH)
  {
      Serial.println(\"Motion ended!\");  // print on output change
      pirState = LOW;
    }
  }
}



这是似乎给出错误读取的代码
代码：全选void do_board_function() {   // This boards function is to get and send DHT temp/humity to MQTT
  Serial.println(\"\");
  Serial.println(\"Starting Board Functions\");
  //////START - TEMP + HUM//////
  float readt = dht.readTemperature();
  delay(2000);
  float readh = dht.readHumidity();
  // Check if any reads failed and exit early (to try again).
  if (isnan(readt)) {   
    Serial.println(\"Failed to read from DHT sensor!\");
  }
  else {
    Serial.print(\"Temperature = \");
    Serial.print(readt);
    Serial.print(\" .... \");
    Serial.print(\"Humidity = \");
    Serial.print(readh);
    Serial.println();
    String temp_strt = String(readt);
    String hum_strt = String(readh);
    temp_strt.toCharArray(temp, temp_strt.length() + 1); //packaging up the data to publish to mqtt
    String temp_strh = String(readh);
    hum_strt.toCharArray(hum, hum_strt.length() + 1); //packaging up the data to publish to mqtt
    // String MQTTPublish = String(\"Temperature is\" + t + \"Humidity is\" + h);
    client.publish(Topic_DataMessagesTemp, temp);
    client.publish(Topic_DataMessagesHum, hum);
    //////END - TEMP + HUM//////


    //New Motion Sensor code
   val = digitalRead(MOTIONPIN);  // read input value
  Serial.println((String)\"the value of val is \" +val);
  if (val == HIGH)  // check if the input is HIGH
  {            
    Serial.println(\"Motion is on\");
    if (pirState == LOW)
  {
      Serial.println(\"Motion detected!\"); // print on output change
      pirState = HIGH;
    }
  }
  else
  {
    if (pirState == HIGH)
  {
      Serial.println(\"Motion ended!\");  // print on output change
      pirState = LOW;
    }
  }