Ph 传感器始终显示“0”，但仅在此特定代码中

Question

我得到了这个学校项目，我制作了这个与谷歌表格链接的简单代码，问题是一个传感器给了我正确的读数，而另一个传感器只显示“0” 传感器本身工作正常，接线正常并且校准良好。我已经只使用了代码的 ph 部分来查看读数，并且确实有效，显示了 0 以上的不同值

#include <Arduino.h>
#include <WiFi.h>
#include "time.h"
#include <ESP_Google_Sheet_Client.h>
#include <OneWire.h>
#include <DallasTemperature.h>
#include <GS_SDHelper.h>

#define WIFI_SSID "Sample"
#define WIFI_PASSWORD "Sample123"
#define PROJECT_ID "SampleIDLOL"
#define CLIENT_EMAIL "SampleMailLOL"

const char PRIVATE_KEY[] PROGMEM = "SampleKeyLOL";
const char spreadsheetId[] = "SampleIDLOL";
unsigned long lastTime = 0;  
unsigned long timerDelay = 30000;

void tokenStatusCallback(TokenInfo info);

int phpin = 4;
int tempPin = 5;
int redPin = 18;
int greenPin = 19;
int bluePin = 21;
int buzzer = 13;
float calibrationFactor = 3.5;
float offset = 0.0

OneWire oneWireObjeto(tempPin);
DallasTemperature sensorDS18B20(&oneWireObjeto);

const char* ntpServer = "pool.ntp.org";
unsigned long epochTime; 

unsigned long getTime() {
    time_t now;
    struct tm timeinfo;
    if (!getLocalTime(&timeinfo)) {
        //Serial.println("Failed to obtain time");
        return(0);
    }
    time(&now);
    return now;
}

void setup() {
    pinMode(phpin,INPUT);
    pinMode(tempPin, INPUT);
    pinMode(redPin, OUTPUT);
    pinMode(greenPin, OUTPUT);
    pinMode(bluePin, OUTPUT);

    Serial.begin(9600);
    Serial.println();
    Serial.println();

    configTime(-18000, 0, ntpServer);

    GSheet.printf("ESP Google Sheet Client v%s\n\n", ESP_GOOGLE_SHEET_CLIENT_VERSION);

    WiFi.setAutoReconnect(true);
    WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
  
    Serial.print("Connecting to Wi-Fi");
    while (WiFi.status() != WL_CONNECTED) {
        Serial.print(".");
        delay(1000);
    }
    Serial.println();
    Serial.print("Connected with IP: ");
    Serial.println(WiFi.localIP());
    Serial.println();

    GSheet.setTokenCallback(tokenStatusCallback);
    GSheet.setPrerefreshSeconds(10 * 60);
    GSheet.begin(CLIENT_EMAIL, PROJECT_ID, PRIVATE_KEY);
    
    sensorDS18B20.begin();
}

void loop() {
    sensorDS18B20.requestTemperatures();
    float temperature = (sensorDS18B20.getTempCByIndex(0));   

    int rawValue = analogRead(phpin);
  
    float voltage = (rawValue * 5.0) / 10230.;
    float phValue = (voltage * calibrationFactor) + offset;

    bool ready = GSheet.ready();

    if (ready && millis() - lastTime > timerDelay) {
        lastTime = millis();

        FirebaseJson response;

        Serial.println("\nAppend spreadsheet values...");
        Serial.println("----------------------------");

        FirebaseJson valueRange;
     
        epochTime = getTime();

        valueRange.add("majorDimension", "COLUMNS");
        valueRange.set("values/[0]/[0]", epochTime);
        valueRange.set("values/[1]/[0]", phValue);
        valueRange.set("values/[2]/[0]", temperature);
        
        bool success = GSheet.values.append(&response /* returned response */, spreadsheetId /* spreadsheet Id to append */, "A3" /* range to append */, &valueRange /* data range to append */);
        if (success) {
            response.toString(Serial, true);
            valueRange.clear();
        }
        else {
            Serial.println(GSheet.errorReason());
        }
        Serial.println();
        Serial.println(ESP.getFreeHeap());
    }

    if (phValue >= 7) { 
        digitalWrite(redPin, LOW);    
        digitalWrite(greenPin, LOW);  
        digitalWrite(bluePin, HIGH);  
        digitalWrite(buzzer, HIGH);      
    }
    if (phValue >= 3 && phValue < 7) {   
        digitalWrite(redPin, LOW);    
        digitalWrite(greenPin,LOW);   
        digitalWrite(bluePin, LOW);   
    }
    if (phValue >= 0 && phValue < 3) {      
        digitalWrite(redPin, HIGH);     
        digitalWrite(greenPin, LOW);    
        digitalWrite(bluePin, LOW);     
    }    
    if (phValue > 6.5) {
        digitalWrite(buzzer, HIGH);
    }
}

void tokenStatusCallback(TokenInfo info) {
    if (info.status == token_status_error) {
        GSheet.printf("Token info: type = %s, status = %s\n", GSheet.getTokenType(info).c_str(), GSheet.getTokenStatus(info).c_str());
        GSheet.printf("Token error: %s\n", GSheet.getTokenError(info).c_str());
    }
    else {
        GSheet.printf("Token info: type = %s, status = %s\n", GSheet.getTokenType(info).c_str(), GSheet.getTokenStatus(info).c_str());
    }
}

谷歌表的代码运行良好，其他传感器读数与纪元时间一起显示良好。 ph 读数每次都显示“0”，不仅在谷歌表中，而且在串行监视器中（如果我包含它）

Answer 1

除了许多代码样式问题之外，在我看来，您已经除以大数（

float voltage = (rawValue * 5.0) / 10230.

：10230.0）。这会导致一个数字始终在0和1之间，即使在校准因子和偏移量之后也是如此添加，始终打开红色 LED。

在排除这些类型的错误时，您应该打印出电压和 pH 值，以查看它们的值以及您的系统如何反应。当您让编译器进行从浮点/双精度到整数的隐式类型转换时，这也将帮助您解决舍入错误。