Zum Stromverbrauch (Arduino Pro Mini (3,3V/8MHz, Power-LED entfernt; RFM95, +BMP180, ~4,4V LiPo über den Spannungsregler vom Arduino):
-2,9mA ohne Aktivität
-20-80mA während der ersten 2-3 Minuten bis die Daten übetragen sind.
Aktueller Sketch mit sehr moderater Optimierung des Stromverbrauchs (Vor allem 900 Sekunden Sleep):
// Enable debug prints to serial monitor
#define MY_DEBUG
// Enable and select radio type attached
//#define MY_RADIO_NRF24
//#define MY_RADIO_NRF5_ESB
//#define MY_RADIO_RFM69
#define MY_RADIO_RFM95
//#define MY_DEBUG_VERBOSE_RFM95
#define MY_RADIO_RFM95
#define MY_TRANSPORT_STATE_TIMEOUT_MS (3*1000ul)
#define RFM95_RETRY_TIMEOUT_MS (3000ul)
#define MY_RFM95_FREQUENCY (RFM95_868MHZ)
#define MY_RFM95_MODEM_CONFIGRUATION RFM95_BW125CR48SF4096
// BW125CR45SF128 Default, medium range 50ms
// BW500CR45SF128 Fast, short range 15ms
// BW31_25CR48SF512 Slow, long range 900ms
// BW125CR48SF4096 Slow, long range 1500ms
// https://docs.google.com/spreadsheets/d/1voGAtQAjC1qBmaVuP1ApNKs1ekgUjavHuVQIXyYSvNc
//#define MY_DEBUG_VERBOSE_RFM95_REGISTERS
//#define MY_RFM95_ATC_TARGET_RSSI (-70) // target RSSI -70dBm
//#define MY_RFM95_MAX_POWER_LEVEL_DBM (20) // max. TX power 10dBm = 10mW
#include <SPI.h>
#include <MySensors.h>
#include <Wire.h>
#include <Adafruit_BMP085.h>
#define BARO_CHILD 0
#define TEMP_CHILD 1
const float ALTITUDE = 688; // <-- adapt this value to your own location's altitude.
// Sleep time between reads (in seconds). Do not change this value as the forecast algorithm needs a sample every minute.
const unsigned long SLEEP_TIME = 900000;
Adafruit_BMP085 bmp = Adafruit_BMP085(); // Digital Pressure Sensor
float lastPressure = -1;
float lastTemp = -1;
int lastForecast = -1;
const int LAST_SAMPLES_COUNT = 5;
float lastPressureSamples[LAST_SAMPLES_COUNT];
// this CONVERSION_FACTOR is used to convert from Pa to kPa in forecast algorithm
// get kPa/h be dividing hPa by 10
#define CONVERSION_FACTOR (1.0/10.0)
int minuteCount = 0;
bool firstRound = true;
// average value is used in forecast algorithm.
float pressureAvg;
// average after 2 hours is used as reference value for the next iteration.
float pressureAvg2;
float dP_dt;
bool metric;
MyMessage tempMsg(TEMP_CHILD, V_TEMP);
MyMessage pressureMsg(BARO_CHILD, V_PRESSURE);
MyMessage forecastMsg(BARO_CHILD, V_FORECAST);
void setup()
{
if (!bmp.begin())
{
Serial.println("Could not find a valid BMP085 sensor, check wiring!");
while (1) {}
}
}
void presentation() {
// Send the sketch version information to the gateway and Controller
sendSketchInfo("PressSensLoRa", "0.0.1");
// Register sensors to gw (they will be created as child devices)
present(BARO_CHILD, S_BARO);
present(TEMP_CHILD, S_TEMP);
}
void loop()
{
float pressure = bmp.readSealevelPressure(ALTITUDE) / 100.0;
float temperature = bmp.readTemperature();
Serial.print("Temperature = ");
Serial.print(temperature);
Serial.println(" *C");
Serial.print("Pressure = ");
Serial.print(pressure);
Serial.println(" hPa");
if (temperature != lastTemp)
{
send(tempMsg.set(temperature, 1));
lastTemp = temperature;
}
if (pressure != lastPressure)
{
send(pressureMsg.set(pressure, 0));
lastPressure = pressure;
}
sleep(SLEEP_TIME);
}
