Jens Schmidt / MicrobitIAQ

uses BBC micro:bit to measure and display indoor air quality using Bosch BME680 and/or Sensirion SGP30

Dependencies:   microbit

uses Bosch BME680 and/or Sensirion SGP30 sensors to measure indor air quality

sensors should be connected to BBC micro:bit using i2c

commands are received and data is being sent using uBit / nordic radio protocol

display ---

last line always indicates: - first dot: bme680 detected - second dot: sgp30 detected - third dot: sgp 30 setting humidity/temperature - fourth dor: sgp30 measuring - fith dot: bme680 measuring

the detect dots should be in a stable state (not blinking) the measuring dots should be blinking (constant light means: measurement failed)

if only one bme680 is present: - first 3 lines indicate gas resistence (air quality / more dots == worse quality) - fourth line indicates humidity level

if only sgp30 is present: - first two lines indicate SGP30 VOC level - third and fourth line indicate sgp30 CO2 level

if both sensors are present: - first line indicates SGP30 VOC level - second line line indicates sgp30 CO2 level - third line indicates bme680 gas resistence (air quality) - fourth line indicates bme 680 humidity level

buttons - B display state, switches betweeen - full bright - low light - display off

AB reset sgp30 baseline in non volatile storage

data logging -- during measurements the minimum and mximum values for each measured value (temperature, air pressure, humidity,gas resistance, VOC, CO2) are being stored in non volatile storage those (and the last measurement results) are being shown when btn A has been pressed

math/gleitenderDurchschnitt.cpp@31:3284adaf4804, 2019-02-02 (annotated)

Committer:
jsa1969
Date:
Sat Feb 02 11:05:17 2019 +0000
Revision:
31:3284adaf4804
implements math function: gleitender Durchschnitt

Who changed what in which revision?

UserRevisionLine numberNew contents of line
jsa1969 31:3284adaf4804 1 #include "mbed.h"
jsa1969 31:3284adaf4804 2
jsa1969 31:3284adaf4804 3 #include "gleitenderDurchschnitt.h"
jsa1969 31:3284adaf4804 4
jsa1969 31:3284adaf4804 5 GleitenderDuchschnitt::GleitenderDuchschnitt(const int maxElements){
jsa1969 31:3284adaf4804 6 _maxElements = maxElements;
jsa1969 31:3284adaf4804 7 _values = new uint32_t(maxElements);
jsa1969 31:3284adaf4804 8 for (int i = 0 ; i < maxElements ; ++i) {
jsa1969 31:3284adaf4804 9 _values[i] = INVALID;
jsa1969 31:3284adaf4804 10 }
jsa1969 31:3284adaf4804 11 currentDurchschnitt = INVALID;
jsa1969 31:3284adaf4804 12 _currentIndex = 0;
jsa1969 31:3284adaf4804 13 }
jsa1969 31:3284adaf4804 14
jsa1969 31:3284adaf4804 15 uint32_t GleitenderDuchschnitt::durchschnitt() {
jsa1969 31:3284adaf4804 16 return currentDurchschnitt;
jsa1969 31:3284adaf4804 17 }
jsa1969 31:3284adaf4804 18
jsa1969 31:3284adaf4804 19 void GleitenderDuchschnitt::add(const uint32_t value) {
jsa1969 31:3284adaf4804 20 _values[_currentIndex] = value;
jsa1969 31:3284adaf4804 21 if (++_currentIndex >= _maxElements) {
jsa1969 31:3284adaf4804 22 _currentIndex = 0;
jsa1969 31:3284adaf4804 23 }
jsa1969 31:3284adaf4804 24 calcDurchschnitt();
jsa1969 31:3284adaf4804 25 }
jsa1969 31:3284adaf4804 26
jsa1969 31:3284adaf4804 27 void GleitenderDuchschnitt::calcDurchschnitt() {
jsa1969 31:3284adaf4804 28 int validVals = 0;
jsa1969 31:3284adaf4804 29 uint32_t sum = 0;
jsa1969 31:3284adaf4804 30
jsa1969 31:3284adaf4804 31 for (int i = 0 ; i < _maxElements ; ++i) {
jsa1969 31:3284adaf4804 32 if (_values[i] != INVALID) {
jsa1969 31:3284adaf4804 33 ++validVals;
jsa1969 31:3284adaf4804 34 sum += _values[i];
jsa1969 31:3284adaf4804 35 }
jsa1969 31:3284adaf4804 36 }
jsa1969 31:3284adaf4804 37 if (validVals > 0) {
jsa1969 31:3284adaf4804 38 currentDurchschnitt = sum / validVals;
jsa1969 31:3284adaf4804 39 }
jsa1969 31:3284adaf4804 40 }