ThingSpeak

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Hi guys, One way of posting multiple data at once is bulk-write JSON Data. There is an example re this here, which shows how to update the data on ESP8266 frequently. I can't work out step 8, which expalins how to update the JSON file. Could you please provide me a reference/tutorial/manual so that I can upskill myself to work this out? Also, I need to send the temperature readings (variables). Do I need to define the temp data as object or array on JSON? Below provides the code for step 8. // Updates the josnBuffer with data void updatesJson(char* jsonBuffer){ /* JSON format for updates paramter in the API * This examples uses the relative timestamp as it uses the "delta_t". You can also provide the absolute timestamp using the "created_at" parameter * instead of "delta_t". * "[{\"delta_t\":0,\"field1\":-70},{\"delta_t\":3,\"field1\":-66}]" */ // Format the jsonBuffer as noted above strcat(jsonBuffer,"{\"delta_t\":"); unsigned long deltaT = (millis() - lastUpdateTime)/1000; size_t lengthT = String(deltaT).length(); char temp[4]; String(deltaT).toCharArray(temp,lengthT+1); strcat(jsonBuffer,temp); strcat(jsonBuffer,","); long rssi = WiFi.RSSI(); strcat(jsonBuffer, "\"field1\":"); lengthT = String(rssi).length(); String(rssi).toCharArray(temp,lengthT+1); strcat(jsonBuffer,temp); strcat(jsonBuffer,"},"); // If posting interval time has reached 2 minutes, update the ThingSpeak channel with your data if (millis() - lastConnectionTime >= postingInterval) { size_t len = strlen(jsonBuffer); jsonBuffer[len-1] = ']'; httpRequest(jsonBuffer); } lastUpdateTime = millis(); // Update the last update time }