功能介绍
1.eco2,tvoc,温湿度检测
大家可以根据实际情况减去外部环境影响的温度.
下面是代码:
#include <Wire.h>
#include "Adafruit_SGP30.h"
#include <ESP8266WiFi.h>
#include "Adafruit_SHT31.h"
#include <PubSubClient.h>
Adafruit_SGP30 sgp;
#define AP_SSID "abc" // 这里改成你的wifi名字
#define AP_PSW "123456" // 这里改成你的wifi密码
#define MQTT_SERVER "mqtt.com"
#define MQTT_SERVERPORT 1883
#define MQTT_USERNAME "test"
#define MQTT_PASSWD "test"
#define MQTT_CLIENT_ID "esp8266_sgp30"
bool enableHeater = false;
uint8_t loopCnt = 0;
Adafruit_SHT31 sht31 = Adafruit_SHT31();
/* return absolute humidity [mg/m^3] with approximation formula
@param temperature [°C]
@param humidity [%RH]
*/
uint32_t getAbsoluteHumidity(float temperature, float humidity) {
// approximation formula from Sensirion SGP30 Driver Integration chapter 3.15
const float absoluteHumidity = 216.7f * ((humidity / 100.0f) * 6.112f * exp((17.62f * temperature) / (243.12f + temperature)) / (273.15f + temperature)); // [g/m^3]
const uint32_t absoluteHumidityScaled = static_cast<uint32_t>(1000.0f * absoluteHumidity); // [mg/m^3]
return absoluteHumidityScaled;
}
WiFiClient espClient;
void callback(char* topic, byte* payload, unsigned int length) {
}
PubSubClient client(MQTT_SERVER, MQTT_SERVERPORT, callback, espClient);
void setup() {
Serial.begin(9600);
while (!Serial)
delay(10); // 将暂停“零”，“莱昂纳多”等，直到打开串行控制台
// 启动STA模式，并连接到wifi网络
WiFi.begin(AP_SSID, AP_PSW);
// 判断网络状态是否连接上，没连接上就延时500ms，并且打出一个点，模拟连接过程
// 加入网络一直都连不上 是否可以做个判断，由你们自己实现
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.println(".");
}
// 输出station IP地址，这里的IP地址由DHCP分配
Serial.println(WiFi.localIP());
// sht31
if (! sht31.begin(0x44)) { // Set to 0x45 for alternate i2c addr
Serial.println("Couldn't find SHT31");
// while (1) delay(1);
}
// Serial.print("Heater Enabled State: ");
// if (sht31.isHeaterEnabled())
// Serial.println("ENABLED");
// else
// Serial.println("DISABLED");
// Serial.println("SGP30 test");
if (! sgp.begin()) {
Serial.println("Sensor not found :(");
// while (1);
}
// Serial.print("Found SGP30 serial #");
Serial.print(sgp.serialnumber[0], HEX);
Serial.print(sgp.serialnumber[1], HEX);
Serial.println(sgp.serialnumber[2], HEX);
// If you have a baseline measurement from before you can assign it to start, to 'self-calibrate'
// sgp.setIAQBaseline(0x8E68, 0x8F41); // Will vary for each sensor!
}
int counter = 0;
void loop() {
// sht31
float t = sht31.readTemperature();
float h = sht31.readHumidity();
char temperature[32];
float temperature_tmp;
if (! isnan(t)) { // check if 'is not a number'
// Serial.print("Temp *C = "); Serial.print(t); Serial.print("\t\t");
temperature_tmp = float(t);
Serial.print(temperature_tmp); Serial.print("*C\t");
sprintf(temperature, "%f", temperature_tmp);
Serial.print(temperature); Serial.print("\t");
} else {
Serial.println("Failed to read temperature");
}
char humidity[32];
float humidity_tmp;
if (! isnan(h)) { // check if 'is not a number'
// Serial.print("Hum. % = "); Serial.pr intln(h);
humidity_tmp = float(h);
Serial.print(humidity_tmp); Serial.print("%\t");
sprintf(humidity, "%f", humidity_tmp);
Serial.print(humidity); Serial.print("\t");
} else {
Serial.println("Failed to read humidity");
}
delay(1000);
// 每30秒切换一次加热器启用状态
// 启用加热器后，温度会升高约3.0摄氏度
if (++loopCnt == 30) {
enableHeater = !enableHeater;
sht31.heater(enableHeater);
// Serial.print("Heater Enabled State: ");
// if (sht31.isHeaterEnabled())
// Serial.println("ENABLED");
// else
// Serial.println("DISABLED");
loopCnt = 0;
}
// sgp30
// If you have a temperature / humidity sensor, you can set the absolute humidity to enable the humditiy compensation for the air quality signals
// 温湿度补偿
// float temperature = 26.3; // [°C]
// float humidity = 74.8; // [%RH]
Serial.print("\n计算:\n");
Serial.print(temperature_tmp);
Serial.print("\n");
Serial.print( humidity_tmp);
Serial.print("\n");
sgp.setHumidity(getAbsoluteHumidity(temperature_tmp, humidity_tmp));
if (! sgp.IAQmeasure()) {
Serial.println("Measurement failed");
return;
}
Serial.print("TVOC "); Serial.print(sgp.TVOC); Serial.print(" ppb\t");
Serial.print("eCO2 "); Serial.print(sgp.eCO2); Serial.println(" ppm\t");
char tvoc[8], eco2[8];
sprintf(tvoc, "%d", sgp.TVOC);
sprintf(eco2, "%d", sgp.eCO2);
if (! sgp.IAQmeasureRaw()) {
Serial.println("Raw Measurement failed");
return;
}
// Serial.print("Raw H2 "); Serial.print(sgp.rawH2); Serial.print(" \t"); // 原始h2
// Serial.print("Raw Ethanol "); Serial.print(sgp.rawEthanol); Serial.println(""); // 原始乙醇
delay(5000);
counter++;
if (counter == 30) {
counter = 0;
uint16_t TVOC_base, eCO2_base;
if (! sgp.getIAQBaseline(&eCO2_base, &TVOC_base)) {
Serial.println("Failed to get baseline readings");
return;
}
// Serial.print("****Baseline values: eCO2: 0x"); Serial.print(eCO2_base, HEX); // 基准值
// Serial.print(" & TVOC: 0x"); Serial.println(TVOC_base, HEX);
}
delay(3000);
if (client.connect(MQTT_CLIENT_ID, MQTT_USERNAME, MQTT_PASSWD)) {
Serial.println("MQTT Connected!");
// topic
client.publish("/esp8266/sgp30/tvoc", tvoc);
client.publish("/esp8266/sgp30/eco_two", eco2);
client.publish("/esp8266/sgp30/temperature", temperature);
client.publish("/esp8266/sgp30/humidity", humidity);
}
}