Add example for async API

examples/bme680async/bme680async.ino

@@ -0,0 +1,101 @@
+/***************************************************************************
+  This is a library for the BME680 gas, humidity, temperature & pressure sensor
+
+  Designed specifically to work with the Adafruit BME680 Breakout
+  ----> http://www.adafruit.com/products/3660
+
+  These sensors use I2C or SPI to communicate, 2 or 4 pins are required
+  to interface.
+
+  Adafruit invests time and resources providing this open source code,
+  please support Adafruit and open-source hardware by purchasing products
+  from Adafruit!
+
+  Written by Limor Fried & Kevin Townsend for Adafruit Industries.
+  BSD license, all text above must be included in any redistribution
+ ***************************************************************************/
+
+#include <Wire.h>
+#include <SPI.h>
+#include <Adafruit_Sensor.h>
+#include "Adafruit_BME680.h"
+
+#define BME_SCK 13
+#define BME_MISO 12
+#define BME_MOSI 11
+#define BME_CS 10
+
+#define SEALEVELPRESSURE_HPA (1013.25)
+
+Adafruit_BME680 bme; // I2C
+//Adafruit_BME680 bme(BME_CS); // hardware SPI
+//Adafruit_BME680 bme(BME_CS, BME_MOSI, BME_MISO, BME_SCK);
+
+void setup() {
+  Serial.begin(9600);
+  while (!Serial);
+  Serial.println(F("BME680 async test"));
+
+  if (!bme.begin()) {
+    Serial.println(F("Could not find a valid BME680 sensor, check wiring!"));
+    while (1);
+  }
+
+  // Set up oversampling and filter initialization
+  bme.setTemperatureOversampling(BME680_OS_8X);
+  bme.setHumidityOversampling(BME680_OS_2X);
+  bme.setPressureOversampling(BME680_OS_4X);
+  bme.setIIRFilterSize(BME680_FILTER_SIZE_3);
+  bme.setGasHeater(320, 150); // 320*C for 150 ms
+}
+
+void loop() {
+  // Tell BME680 to begin measurement.
+  unsigned long endTime = bme.beginReading();
+  if (endTime == 0) {
+    Serial.println(F("Failed to begin reading :("));
+    return;
+  }
+  Serial.print(F("Reading started at "));
+  Serial.print(millis());
+  Serial.print(F(" and will finish at "));
+  Serial.println(endTime);
+
+  Serial.println(F("You can do other work during BME680 measurement."));
+  delay(50); // This represents parallel work.
+  // There's no need to delay() until millis() >= endTime: bme.endReading()
+  // takes care of that. It's okay for parallel work to take longer than
+  // BME680's measurement time.
+
+  // Obtain measurement results from BME680. Note that this operation isn't
+  // instantaneous even if milli() >= endTime due to I2C/SPI latency.
+  if (!bme.endReading()) {
+    Serial.println(F("Failed to complete reading :("));
+    return;
+  }
+  Serial.print(F("Reading completed at "));
+  Serial.println(millis());
+
+  Serial.print(F("Temperature = "));
+  Serial.print(bme.temperature);
+  Serial.println(F(" *C"));
+
+  Serial.print(F("Pressure = "));
+  Serial.print(bme.pressure / 100.0);
+  Serial.println(F(" hPa"));
+
+  Serial.print(F("Humidity = "));
+  Serial.print(bme.humidity);
+  Serial.println(F(" %"));
+
+  Serial.print(F("Gas = "));
+  Serial.print(bme.gas_resistance / 1000.0);
+  Serial.println(F(" KOhms"));
+
+  Serial.print(F("Approx. Altitude = "));
+  Serial.print(bme.readAltitude(SEALEVELPRESSURE_HPA));
+  Serial.println(F(" m"));
+
+  Serial.println();
+  delay(2000);
+}