使用esp8266作为I2C传感器的主机

对于我的室外传感器，我使用了一个RaspberryPi，它具有通过I ² C连接的BMP180 + TSL2561，将传感器数据作为MQTT消息传输。

在法兰克福以代码为中心的办公室举行的物联网会议期间，我们讨论了esp8266的用法，我很高兴能得到它并使用它。

很快就知道esp8266是非常好的硬件，我计划更换充当网络传感器主机的Raspberry Pi。借助esp8266的wifi功能，我仍然可以使用MQTT方法运行I ² C传感器。

例如当前安装在户外的Raspberry Pi将值发送给这些主题

sweethome /传感器/室外/温度
sweethome /传感器/室外/压力
sweethome /传感器/室外/ lux

如果让esp8266发布到这些主题，我的网络其余部分也不会意识到有变化...

计划：保留I


	树莓派	HUZAAH ESP8266突破
SD卡：	40€	10€
无线局域网	8€	–
总：	52€	10€
能量消耗：	3W	1瓦

硬件

Adafruit HUZZAH ESP8266突破
Adafruit BMP180（温度+压力）
Adafruit TSL2561（光度）
Adafruit FTDI Friend（USB连接器）

集成开发环境

Arduino IDE

图书馆

几乎所有库都可以通过Arduino IDE库管理器轻松安装。除esp8266支持外，还必须设置其他董事会管理器URL： http ://arduino.esp8266.com/stable/package_esp8266com_index.json

ESP8266WiFi
Adafruit BMP085统一
Adafruit TSL2561统一
Adafruit MQTT库

软件

esp8266分支具有对LUA的内置支持，但我决定将其刷新以准备与Arduino IDE和C ++一起使用（主要是因为Adafruit都很好地支持了驱动程序）。

#include <ESP8266WiFi.h>
#include "Adafruit_MQTT.h"
#include "Adafruit_MQTT_Client.h"
#include <Wire.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BMP085_U.h>
#include <Adafruit_TSL2561_U.h>/************************* WiFi Access Point *********************************/#define WLAN_SSID       "Lummerland"
#define WLAN_PASS       "****************"/************************* MQTT Broker Setup *********************************/const int MQTT_PORT = 1883;
const char MQTT_SERVER[] PROGMEM    = "192.168.0.61";
const char MQTT_CLIENTID[] PROGMEM  = "ESP-PUBLISHER-SERVICE";
const char MQTT_USERNAME[] PROGMEM  = "********";
const char MQTT_PASSWORD[] PROGMEM  = "********";// Create an ESP8266 WiFiClient class to connect to the MQTT server.
WiFiClient client;Adafruit_MQTT_Client mqtt(&client, MQTT_SERVER, MQTT_PORT, MQTT_CLIENTID, MQTT_USERNAME, MQTT_PASSWORD);/****************************** Feeds ***************************************/
const char TEMPERATURE_FEED[] PROGMEM = "sweethome/sensors/outdoor/temperature";
Adafruit_MQTT_Publish temperature_topic = Adafruit_MQTT_Publish(&mqtt, TEMPERATURE_FEED);const char PRESSURE_FEED[] PROGMEM = "sweethome/sensors/outdoor/pressure";
Adafruit_MQTT_Publish pressure_topic = Adafruit_MQTT_Publish(&mqtt, PRESSURE_FEED);const char LUMINOSITY_FEED[] PROGMEM = "sweethome/sensors/outdoor/lux";
Adafruit_MQTT_Publish luminosity_topic = Adafruit_MQTT_Publish(&mqtt, LUMINOSITY_FEED);Adafruit_BMP085_Unified bmp = Adafruit_BMP085_Unified(10085);
Adafruit_TSL2561_Unified tsl = Adafruit_TSL2561_Unified(TSL2561_ADDR_FLOAT, 12345);/*************************** Sketch Code ************************************/void setup() {Serial.begin(115200);delay(10);Serial.println("Sensor Test");if (!bmp.begin()){Serial.print("Ooops, no BMP180 detected ... Check your wiring or I2C ADDR!");while (1);}else {Serial.println("BMP180 ready.");}if (!tsl.begin()){Serial.print("Ooops, no TSL2561 detected ... Check your wiring or I2C ADDR!");while (1);}else {Serial.println("TSL2561 ready.");}configureTSL2561();// Connect to WiFi access point.Serial.println();Serial.print("Connecting to ");Serial.println(WLAN_SSID);WiFi.begin(WLAN_SSID, WLAN_PASS);while (WiFi.status() != WL_CONNECTED) {delay(500);Serial.print(".");}Serial.println();Serial.println("WiFi connected");Serial.println("IP address: "); Serial.println(WiFi.localIP());
}void loop() {MQTT_connect();/* Get a new sensor event */sensors_event_t bmpEvent;bmp.getEvent(&bmpEvent);if (bmpEvent.pressure){float temperature;bmp.getTemperature(&temperature);Serial.print("Temperature: ");Serial.print(temperature);Serial.println(" C");Serial.print("Publish Temperature: ");if (! temperature_topic.publish(temperature)) {Serial.println("Failed");} else {Serial.println("OK!");}float pressure = bmpEvent.pressure;Serial.print("Pressure:    ");Serial.print(pressure);Serial.println(" hPa");Serial.print("Publish Pressure: ");if (! pressure_topic.publish(pressure)) {Serial.println("Failed");} else {Serial.println("OK!");}}else{Serial.println("Sensor error");}sensors_event_t tslEvent;tsl.getEvent(&tslEvent);unsigned int luminosity = 0;if (tslEvent.light){luminosity = tslEvent.light;}Serial.print("Luminosity:   ");Serial.print(luminosity);Serial.println(" lux");Serial.print("Publish Luminosity: ");if (! luminosity_topic.publish(luminosity)) {Serial.println("Failed");} else {Serial.println("OK!");}delay(5000);
}void configureTSL2561()
{/* You can also manually set the gain or enable auto-gain support */// tsl.setGain(TSL2561_GAIN_1X);      /* No gain ... use in bright light to avoid sensor saturation */// tsl.setGain(TSL2561_GAIN_16X);     /* 16x gain ... use in low light to boost sensitivity */tsl.enableAutoRange(true);            /* Auto-gain ... switches automatically between 1x and 16x *//* Changing the integration time gives you better sensor resolution (402ms = 16-bit data) */tsl.setIntegrationTime(TSL2561_INTEGRATIONTIME_13MS);      /* fast but low resolution */// tsl.setIntegrationTime(TSL2561_INTEGRATIONTIME_101MS);  /* medium resolution and speed   */// tsl.setIntegrationTime(TSL2561_INTEGRATIONTIME_402MS);  /* 16-bit data but slowest conversions */
}void MQTT_connect() {int8_t ret;// Stop if already connected.if (mqtt.connected()) {return;}Serial.print("Connecting to MQTT... ");while ((ret = mqtt.connect()) != 0) { // connect will return 0 for connectedswitch (ret) {case 1: Serial.println("Wrong protocol"); break;case 2: Serial.println("ID rejected"); break;case 3: Serial.println("Server unavailable"); break;case 4: Serial.println("Bad user/password"); break;case 5: Serial.println("Not authenticated"); break;case 6: Serial.println("Failed to subscribe"); break;default: Serial.print("Couldn't connect to server, code: ");Serial.println(ret);break;}Serial.println("Retrying MQTT connection in 5 seconds...");mqtt.disconnect();delay(5000);  // wait 5 seconds}Serial.println("MQTT Connected!");
}

要使程序在esp板上运行，您必须

使esp8266进入Flash模式

按住+按住“重置”按钮，然后按+按住“ GPIO0”按钮，然后释放“重置”按钮，然后释放“ GPIO0”按钮 ->红色LED点亮（亮度较低）

准备上传

打开串行监视器以查看发生了什么：

注意“ Board”，“ CPU Frequency”，“ Upload Speed”和“ Port”设置！

在上传之前，您可以通过单击“验证”来构建程序：

然后开始上传：

程序立即启动，并且串行监视器显示发生了什么：

要调试/监视MQTT消息，我正在使用MQTT.fx （当然;-)）：

无需对我的网络的其他组件进行任何更改。替换对（移动）客户端也是透明的：

翻译自: https://www.javacodegeeks.com/2015/09/using-the-esp8266-as-host-for-i2c-sensors.html