This shows the use of a "ThingSpeak logger" object. Data is sent to ThingSpeak using MQTT.
Unique Features of the ThingSpeak Example A single logger publishes data to ThingSpeak. Uses an Espressif ESP8266 to publish data. To Use this Example Get ThingSpeak Credentials Log in or create an account on ThingSpeakNOTE: There is no free tier on ThingSpeak for organizational or commercial use and the personal free tier is very limited! Create a channel on ThingSpeak with fields to receive your data.Note the channel number, this is needed in the code! Add a new MQTT device to publish to.Copy or save the MQTT client id, user name, and password! Prepare and set up PlatformIO Create a new PlatformIO project Replace the contents of the platformio.ini for your new project with the platformio.ini file in the examples/logging_to_ThingSpeak folder on GitHub.It is important that your PlatformIO configuration has the lib_ldf_mode and build flags set as they are in the example. Without this, the program won't compile. Open logging_ to_ ThingSpeak.ino and save it to your computer.After opening the link, you should be able to right click anywhere on the page and select "Save Page As". Move it into the src directory of your project. Delete main.cpp in that folder. Modify the Example Modify logging_to_ThingSpeak.ino to have the modem, sensor, and variable objects that you are interested in.This example is written for an ESP8266 (wifi) modem. Change this to whatever modem you are using. Paste-able chunks of code for each modem are available in the individual sensor documentation or in the menu a la carte example. Don't forget to put in your wifi username/password or cellular APN! This example is written for a Campbell OBS3+ and a Meter Hydros 21. Remove those sensors if you are not using them and add code for all of your sensors. See the pages for the individual sensors in the documentation for code snippets/examples.Remember, no more than 8 variables/fields can be sent to a single ThingSpeak channel. If you want to send data to multiple channels, you must create individual logger objects with unique publishers attached for each channel you want to send to. Make sure the pin numbers and serial ports selected in your code match with how things are physically attached to your board! Order the variables in your variable array in the same order as your fields are on ThingSpeak.This order is crucial . The results from the variables in the VariableArray will be sent to ThingSpeak in the order they are in the array; that is, the first variable in the array will be sent as Field1, the second as Field2, etc. Any UUID's or custom variable codes are ignored for ThingSpeak. They will only appear in the header of your file on the SD card. Find this information for your ThingSpeak account and channel and put it into logging_to_ThingSpeak.ino: 1 const char * thingSpeakClientName = "XXXXXXXXXXXXXXXX" ; // Your MQTT API Key from Account > MyProfile.
2 const char * thingSpeakMQTTUser = "XXXXXXXXXXXXXXXX" ; // The Write API Key for your channel
3 const char * thingSpeakMQTTPassword = "XXXXXXXXXXXXXXXX" ; // The numeric channel id for your channel
4 const char * thingSpeakChannelID = "######" ; // The numeric channel id for your channel
Upload! Test everything at home before deploying out in the wild! PlatformIO Configuration 1 ; PlatformIO Project Configuration File
3 ; Build options: build flags, source filter
4 ; Upload options: custom upload port, speed and extra flags
5 ; Library options: dependencies, extra library storages
6 ; Advanced options: extra scripting
8 ; Please visit documentation for the other options and examples
9 ; http://docs.platformio.org/page/projectconf.html
12 description = ModularSensors example sending data to ThingSpeak
30 -DSDI12_EXTERNAL_PCINT
31 -DNEOSWSERIAL_EXTERNAL_PCINT
32 -DMQTT_MAX_PACKET_SIZE = 240
33 -DTINY_GSM_RX_BUFFER = 64
36 envirodiy/EnviroDIY_ModularSensors
37 ; ^^ Use this when working from an official release of the library
38 ; https://github.com/EnviroDIY/ModularSensors.git#develop
39 ; ^^ Use this when if you want to pull from the develop branch
The Complete Code 1 /** =========================================================================
2 * @example{lineno} logging_to_ThingSpeak.ino
3 * @copyright Stroud Water Research Center
4 * @license This example is published under the BSD-3 license.
5 * @author Sara Geleskie Damiano <sdamiano@stroudcenter.org>
7 * @brief Example logging data and publishing to ThingSpeak.
9 * See [the walkthrough page](@ref example_thingspeak) for detailed
12 * @m_examplenavigation{example_thingspeak,}
13 * ======================================================================= */
15 // ==========================================================================
17 // ==========================================================================
19 #ifndef TINY_GSM_RX_BUFFER
20 #define TINY_GSM_RX_BUFFER 64
22 #ifndef TINY_GSM_YIELD_MS
23 #define TINY_GSM_YIELD_MS 2
27 // ==========================================================================
28 // Include the libraries required for any data logger
29 // ==========================================================================
30 /** Start [includes] */
31 // The Arduino library is needed for every Arduino program.
34 // Include the main header for ModularSensors
35 #include <ModularSensors.h>
39 // ==========================================================================
40 // Data Logging Options
41 // ==========================================================================
42 /** Start [logging_options] */
43 // The name of this program file
44 const char * sketchName = "logging_to_ThingSpeak.ino" ;
45 // Logger ID, also becomes the prefix for the name of the data file on SD card
46 const char * LoggerID = "XXXXX" ;
47 // How frequently (in minutes) to log data
48 const int8_t loggingInterval = 15 ;
49 // Your logger's timezone.
50 const int8_t timeZone = -5 ; // Eastern Standard Time
51 // NOTE: Daylight savings time will not be applied! Please use standard time!
53 // Set the input and output pins for the logger
54 // NOTE: Use -1 for pins that do not apply
55 const int32_t serialBaud = 115200 ; // Baud rate for debugging
56 const int8_t greenLED = 8 ; // Pin for the green LED
57 const int8_t redLED = 9 ; // Pin for the red LED
58 const int8_t buttonPin = 21 ; // Pin for debugging mode (ie, button pin)
59 const int8_t wakePin = 31 ; // MCU interrupt/alarm pin to wake from sleep
61 // Set the wake pin to -1 if you do not want the main processor to sleep.
62 // In a SAMD system where you are using the built-in rtc, set wakePin to 1
63 const int8_t sdCardPwrPin = -1 ; // MCU SD card power pin
64 const int8_t sdCardSSPin = 12 ; // SD card chip select/slave select pin
65 const int8_t sensorPowerPin = 22 ; // MCU pin controlling main sensor power
66 /** End [logging_options] */
69 // ==========================================================================
70 // Wifi/Cellular Modem Options
71 // ==========================================================================
72 /** Start [espressif_esp8266] */
73 // For almost anything based on the Espressif ESP8266 using the AT command
75 #include <modems/EspressifESP8266.h>
76 // Create a reference to the serial port for the modem
77 HardwareSerial & modemSerial = Serial1 ; // Use hardware serial if possible
78 const int32_t modemBaud = 115200 ; // Communication speed of the modem
79 // NOTE: This baud rate too fast for an 8MHz board, like the Mayfly! The
80 // module should be programmed to a slower baud rate or set to auto-baud using
81 // the AT+UART_CUR or AT+UART_DEF command.
83 // Modem Pins - Describe the physical pin connection of your modem to your board
84 // NOTE: Use -1 for pins that do not apply
85 const int8_t modemVccPin = -2 ; // MCU pin controlling modem power
86 const int8_t modemResetPin = 20 ; // MCU pin connected to modem reset pin
87 const int8_t modemLEDPin =
88 redLED ; // MCU pin connected an LED to show modem status
90 // Network connection information
91 const char * wifiId = "xxxxx" ; // The WiFi access point
92 const char * wifiPwd = "xxxxx" ; // The password for connecting to WiFi
94 // Create the loggerModem object
95 EspressifESP8266 modemESP ( & modemSerial , modemVccPin , modemResetPin , wifiId ,
97 // Create an extra reference to the modem by a generic name
98 EspressifESP8266 modem = modemESP ;
99 /** End [espressif_esp8266] */
102 // ==========================================================================
103 // Using the Processor as a Sensor
104 // ==========================================================================
105 /** Start [processor_sensor] */
106 #include <sensors/ProcessorStats.h>
108 // Create the main processor chip "sensor" - for general metadata
109 const char * mcuBoardVersion = "v1.1" ;
110 ProcessorStats mcuBoard ( mcuBoardVersion );
111 /** End [processor_sensor] */
114 // ==========================================================================
115 // Maxim DS3231 RTC (Real Time Clock)
116 // ==========================================================================
118 #include <sensors/MaximDS3231.h>
120 // Create a DS3231 sensor object
121 MaximDS3231 ds3231 ( 1 );
125 // ==========================================================================
126 // Campbell OBS 3 / OBS 3+ Analog Turbidity Sensor
127 // ==========================================================================
129 #include <sensors/CampbellOBS3.h>
131 const int8_t OBS3Power = sensorPowerPin ; // Power pin (-1 if unconnected)
132 const uint8_t OBS3NumberReadings = 10 ;
133 const uint8_t ADSi2c_addr = 0x48 ; // The I2C address of the ADS1115 ADC
134 // Campbell OBS 3+ *Low* Range Calibration in Volts
135 const int8_t OBSLowADSChannel = 0 ; // ADS channel for *low* range output
136 const float OBSLow_A = 0.000E+00 ; // "A" value (X^2) [*low* range]
137 const float OBSLow_B = 1.000E+00 ; // "B" value (X) [*low* range]
138 const float OBSLow_C = 0.000E+00 ; // "C" value [*low* range]
140 // Create a Campbell OBS3+ *low* range sensor object
141 CampbellOBS3 osb3low ( OBS3Power , OBSLowADSChannel , OBSLow_A , OBSLow_B , OBSLow_C ,
142 ADSi2c_addr , OBS3NumberReadings );
145 // Campbell OBS 3+ *High* Range Calibration in Volts
146 const int8_t OBSHighADSChannel = 1 ; // ADS channel for *high* range output
147 const float OBSHigh_A = 0.000E+00 ; // "A" value (X^2) [*high* range]
148 const float OBSHigh_B = 1.000E+00 ; // "B" value (X) [*high* range]
149 const float OBSHigh_C = 0.000E+00 ; // "C" value [*high* range]
151 // Create a Campbell OBS3+ *high* range sensor object
152 CampbellOBS3 osb3high ( OBS3Power , OBSHighADSChannel , OBSHigh_A , OBSHigh_B ,
153 OBSHigh_C , ADSi2c_addr , OBS3NumberReadings );
157 // ==========================================================================
158 // Meter Hydros 21 Conductivity, Temperature, and Depth Sensor
159 // ==========================================================================
160 /** Start [hydros21] */
161 #include <sensors/MeterHydros21.h>
163 const char * hydrosSDI12address = "1" ; // The SDI-12 Address of the Hydros 21
164 const uint8_t hydrosNumberReadings = 6 ; // The number of readings to average
165 const int8_t SDI12Power = sensorPowerPin ; // Power pin (-1 if unconnected)
166 const int8_t SDI12Data = 7 ; // The SDI12 data pin
168 // Create a Meter Hydros 21 sensor object
169 MeterHydros21 hydros21 ( * hydrosSDI12address , SDI12Power , SDI12Data ,
170 hydrosNumberReadings );
174 // ==========================================================================
175 // Creating the Variable Array[s] and Filling with Variable Objects
176 // ==========================================================================
177 /** Start [variable_arrays] */
178 Variable * variableList [] = {
179 new MeterHydros21_Cond ( & hydros21 , "12345678-abcd-1234-ef00-1234567890ab" ),
180 new MeterHydros21_Temp ( & hydros21 , "12345678-abcd-1234-ef00-1234567890ab" ),
181 new MeterHydros21_Depth ( & hydros21 , "12345678-abcd-1234-ef00-1234567890ab" ),
182 new CampbellOBS3_Turbidity ( & osb3low , "12345678-abcd-1234-ef00-1234567890ab" ,
184 new CampbellOBS3_Turbidity (
185 & osb3high , "12345678-abcd-1234-ef00-1234567890ab" , "TurbHigh" ),
186 new ProcessorStats_Battery ( & mcuBoard ,
187 "12345678-abcd-1234-ef00-1234567890ab" ),
188 new MaximDS3231_Temp ( & ds3231 , "12345678-abcd-1234-ef00-1234567890ab" ),
189 new Modem_RSSI ( & modem , "12345678-abcd-1234-ef00-1234567890ab" )};
190 // Count up the number of pointers in the array
191 int variableCount = sizeof ( variableList ) / sizeof ( variableList [ 0 ]);
193 // Create the VariableArray object
194 VariableArray varArray ;
195 /** End [variable_arrays] */
198 // ==========================================================================
199 // The Logger Object[s]
200 // ==========================================================================
201 /** Start [loggers] */
202 // Create a logger instance
207 // ==========================================================================
208 // Creating Data Publisher[s]
209 // ==========================================================================
210 // Create a channel with fields on ThingSpeak in advance
211 // The fields will be sent in exactly the order they are in the variable array.
212 // Any custom name or identifier given to the field on ThingSpeak is irrelevant.
213 // No more than 8 fields of data can go to any one channel. Any fields beyond
214 // the eighth in the array will be ignored.
215 const char * thingSpeakClientName =
216 "XXXXXXXXXXXXXXXX" ; // The client name for your MQTT device
217 const char * thingSpeakMQTTUser =
218 "XXXXXXXXXXXXXXXX" ; // The user name for your MQTT device.
219 const char * thingSpeakMQTTPassword =
220 "XXXXXXXXXXXXXXXX" ; // The password for your MQTT device
221 const char * thingSpeakChannelID =
222 "######" ; // The numeric channel id for your channel
223 const char * thingSpeakAPIKey =
224 "XXXXXXXXXXXXXXXX" ; // The ThingSpeak user REST API key
226 // Create a data publisher for ThingSpeak
227 #include <publishers/ThingSpeakPublisher.h>
228 ThingSpeakPublisher TsMqtt ;
232 // ==========================================================================
234 // ==========================================================================
235 /** Start [working_functions] */
236 // Flashes the LED's on the primary board
237 void greenRedFlash ( uint8_t numFlash = 4 , uint8_t rate = 75 ) {
238 for ( uint8_t i = 0 ; i < numFlash ; i ++ ) {
239 digitalWrite ( greenLED , HIGH );
240 digitalWrite ( redLED , LOW );
242 digitalWrite ( greenLED , LOW );
243 digitalWrite ( redLED , HIGH );
246 digitalWrite ( redLED , LOW );
249 // Reads the battery voltage
250 // NOTE: This will actually return the battery level from the previous update!
251 float getBatteryVoltage () {
252 if ( mcuBoard . sensorValues [ 0 ] == -9999 ) mcuBoard . update ();
253 return mcuBoard . sensorValues [ 0 ];
255 /** End [working_functions] */
258 // ==========================================================================
259 // Arduino Setup Function
260 // ==========================================================================
263 // Start the primary serial connection
264 Serial . begin ( serialBaud );
266 // Print a start-up note to the first serial port
267 Serial . print ( F ( "Now running " ));
268 Serial . print ( sketchName );
269 Serial . print ( F ( " on Logger " ));
270 Serial . println ( LoggerID );
273 Serial . print ( F ( "Using ModularSensors Library version " ));
274 Serial . println ( MODULAR_SENSORS_VERSION );
275 Serial . print ( F ( "TinyGSM Library version " ));
276 Serial . println ( TINYGSM_VERSION );
279 // Start the serial connection with the modem
280 modemSerial . begin ( modemBaud );
282 // Set up pins for the LED's
283 pinMode ( greenLED , OUTPUT );
284 digitalWrite ( greenLED , LOW );
285 pinMode ( redLED , OUTPUT );
286 digitalWrite ( redLED , LOW );
287 // Blink the LEDs to show the board is on and starting up
290 // Set the timezones for the logger/data and the RTC
291 // Logging in the given time zone
292 Logger :: setLoggerTimeZone ( timeZone );
293 // It is STRONGLY RECOMMENDED that you set the RTC to be in UTC (UTC+0)
294 loggerClock :: setRTCOffset ( 0 );
296 // Attach the modem and information pins to the logger
297 dataLogger . attachModem ( modem );
298 modem . setModemLED ( modemLEDPin );
299 dataLogger . setLoggerPins ( wakePin , sdCardSSPin , sdCardPwrPin , buttonPin ,
302 // Begin the variable array[s], logger[s], and publisher[s]
303 varArray . begin ( variableCount , variableList );
304 dataLogger . begin ( LoggerID , loggingInterval , & varArray );
305 TsMqtt . begin ( dataLogger , thingSpeakClientName , thingSpeakMQTTUser ,
306 thingSpeakMQTTPassword , thingSpeakChannelID );
307 TsMqtt . setRESTAPIKey ( thingSpeakAPIKey );
309 // Note: Please change these battery voltages to match your battery
310 // Set up the sensors, except at lowest battery level
311 if ( getBatteryVoltage () > 3.4 ) {
312 Serial . println ( F ( "Setting up sensors..." ));
313 varArray . setupSensors ();
316 // Sync the clock if it isn't valid or we have battery to spare
317 if ( getBatteryVoltage () > 3.55 || ! loggerClock :: isRTCSane ()) {
318 // Set up the modem, synchronize the RTC with NIST, and publish
319 // configuration information to rename the channel and fields.
320 dataLogger . makeInitialConnections ();
323 // Create the log file, adding the default header to it
324 // Do this last so we have the best chance of getting the time correct and
325 // all sensor names correct.
326 // Writing to the SD card can be power intensive, so if we're skipping the
327 // sensor setup we'll skip this too.
328 if ( getBatteryVoltage () > 3.4 ) {
329 Serial . println ( F ( "Setting up file on SD card" ));
330 dataLogger . turnOnSDcard ( true );
331 // true = wait for card to settle after power up
332 dataLogger . createLogFile ( true ); // true = write a new header
333 dataLogger . turnOffSDcard ( true );
334 // true = wait for internal housekeeping after write
337 // Call the processor sleep
338 Serial . println ( F ( "Putting processor to sleep" ));
339 dataLogger . systemSleep ();
344 // ==========================================================================
345 // Arduino Loop Function
346 // ==========================================================================
348 // Use this short loop for simple data logging and sending
350 // Note: Please change these battery voltages to match your battery
351 // At very low battery, just go back to sleep
352 if ( getBatteryVoltage () < 3.4 ) {
353 dataLogger . systemSleep ();
355 // At moderate voltage, log data but don't send it over the modem
356 else if ( getBatteryVoltage () < 3.55 ) {
357 dataLogger . logData ();
359 // If the battery is good, send the data to the world
361 dataLogger . logDataAndPublish ();