From c16d431c8930378dc0e5587321a3976f0f6aa9bb Mon Sep 17 00:00:00 2001
From: klaute <klaute@gmail.com>
Date: Wed, 11 Jul 2018 11:12:53 +0200
Subject: [PATCH] Added the battery voltage code.

---
 firmware/config.h     | 1 +
 firmware/firmware.ino | 7 +++++--
 firmware/influxdb.ino | 6 ++----
 firmware/sensors.ino  | 8 ++++++++
 4 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/firmware/config.h b/firmware/config.h
index a5db2e4..58ad161 100644
--- a/firmware/config.h
+++ b/firmware/config.h
@@ -6,6 +6,7 @@
 #define SENSOR_LIGHT          2
 #define SENSOR_WINDSPEED      3
 #define SENSOR_PRESSURE       4
+#define SENSOR_BAT_VOLTAGE    5
 
 #define UPDATE_SENSOR_INTERVAL_S     10
 #define UPDATE_WEBSERVER_INTVERVAL_S  1
diff --git a/firmware/firmware.ino b/firmware/firmware.ino
index 080f30a..c602082 100644
--- a/firmware/firmware.ino
+++ b/firmware/firmware.ino
@@ -33,7 +33,7 @@
 
 //*************************************************************************//
 
-float currentSensorData[5] = {0.0, 0.0, 0.0, 0.0, 0.0};
+float currentSensorData[6] = {0.0, 0.0, 0.0, 0.0, 0.0, 0.0};
 
 uint16_t update_sensor_cnt    = 0;
 uint16_t update_webserver_cnt = 0;
@@ -56,6 +56,7 @@ void setup() {
   // Pin settings
   pinMode(STATUS_LED_PIN, OUTPUT);
   pinMode(ANEMOMETER_PIN, INPUT_PULLUP);
+  pinMode(A0, INPUT);
 
   // Establish WiFi connection
   String wifiName = "oko-weather-" + String(ESP.getChipId());
@@ -113,6 +114,7 @@ void loop() {
     currentSensorData[SENSOR_LIGHT]       = fetchLight();
     currentSensorData[SENSOR_WINDSPEED]   = fetchWindspeed();
     currentSensorData[SENSOR_PRESSURE]    = fetchPressure();
+    currentSensorData[SENSOR_BAT_VOLTAGE] = getBatteryVoltage();
   
 #ifdef DEBUG
     Serial.println("");
@@ -122,6 +124,7 @@ void loop() {
     Serial.println("Light: " + String(currentSensorData[SENSOR_LIGHT]) + " Lumen");
     Serial.println("Windspeed: " + String(currentSensorData[SENSOR_WINDSPEED]) + " km/h");
     Serial.println("Pressure: " + String(currentSensorData[SENSOR_PRESSURE]) + " hPa");
+    Serial.println("Bat Voltage: " + String(currentSensorData[SENSOR_BAT_VOLTAGE]) + " V");
 #endif
 
     pushToInfluxDB(DEVICE_NAME, currentSensorData);
@@ -136,4 +139,4 @@ void loop() {
 }
 
 //*************************************************************************//
-
+
diff --git a/firmware/influxdb.ino b/firmware/influxdb.ino
index 0c70db0..87b0d75 100755
--- a/firmware/influxdb.ino
+++ b/firmware/influxdb.ino
@@ -5,10 +5,8 @@ void pushToInfluxDB(String device, float sensorValues[]) {
   influxdb.write("weather,device=" + device + " humidity=" + String(sensorValues[SENSOR_HUMIDITY]));
   influxdb.write("weather,device=" + device + " light=" + String(sensorValues[SENSOR_LIGHT]));
   influxdb.write("weather,device=" + device + " windspeed=" + String(sensorValues[SENSOR_WINDSPEED]));
-
-  int tmp = influxdb.write("weather,device=" + device + " pressure=" + String(sensorValues[SENSOR_PRESSURE]));
-
-  Serial.println("Opendb status: " + String(tmp));
+  influxdb.write("weather,device=" + device + " pressure=" + String(sensorValues[SENSOR_PRESSURE]));
+  influxdb.write("weather,device=" + device + " batvoltage=" + String(sensorValues[SENSOR_BAT_VOLTAGE]));
 
 }
 
diff --git a/firmware/sensors.ino b/firmware/sensors.ino
index 770a19e..6838864 100755
--- a/firmware/sensors.ino
+++ b/firmware/sensors.ino
@@ -45,4 +45,12 @@ float fetchWindspeed() {
 
   return (float)anemometerRotations / 5.0 * 2.4;
 }
+
+// Copied from https://arduinodiy.wordpress.com/2016/12/25/monitoring-lipo-battery-voltage-with-wemos-d1-minibattery-shield-and-thingspeak/
+float getBatteryVoltage() {
+  uint16_t raw = analogRead(A0);
+  float volt = raw / 1023.0;
+  volt = volt * 4.2;
+  return volt;
+}