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

i2c/i2c_callbacks.cpp@44:67a19da5f269, 2019-02-13 (annotated)

Committer:
jsa1969
Date:
Wed Feb 13 20:21:38 2019 +0000
Revision:
44:67a19da5f269
Parent:
43:f968ca84d4ed
Child:
46:2fed2865a0f3
more bme tweaking

Who changed what in which revision?

UserRevisionLine numberNew contents of line
jsa1969 0:cef60cc92da0 1 #include "i2c_callbacks.h"
jsa1969 0:cef60cc92da0 2
jsa1969 40:a67a880cb538 3 I2cCallbacks::I2cCallbacks(MicroBit* uBit, MicroBitI2C* i2c){
jsa1969 0:cef60cc92da0 4 _uBit = uBit;
jsa1969 44:67a19da5f269 5 uBit->seedRandom();
jsa1969 44:67a19da5f269 6 _currentlock = 0;
jsa1969 44:67a19da5f269 7
jsa1969 40:a67a880cb538 8 if (i2c == NULL) {
jsa1969 40:a67a880cb538 9 _i2c = &(_uBit->i2c);
jsa1969 40:a67a880cb538 10 }
jsa1969 40:a67a880cb538 11 else {
jsa1969 40:a67a880cb538 12 _i2c = i2c;
jsa1969 40:a67a880cb538 13 }
jsa1969 0:cef60cc92da0 14 }
jsa1969 0:cef60cc92da0 15
jsa1969 44:67a19da5f269 16 int I2cCallbacks::read(const uint8_t address, const uint8_t reg, uint8_t *buffer, const uint16_t length, int lock){
jsa1969 44:67a19da5f269 17 if (buffer == NULL || length <= 0 || lock!=_currentlock)
jsa1969 0:cef60cc92da0 18 return MICROBIT_INVALID_PARAMETER;
jsa1969 42:ce269f988ac8 19
jsa1969 44:67a19da5f269 20 int result = _i2c->write(address, (const char *)&reg, 1, true);
jsa1969 42:ce269f988ac8 21 if (result == 0)
jsa1969 42:ce269f988ac8 22 result = _i2c->read(address, (char *)buffer, length);
jsa1969 42:ce269f988ac8 23
jsa1969 42:ce269f988ac8 24 return result != 0 ? MICROBIT_I2C_ERROR : MICROBIT_OK;
jsa1969 0:cef60cc92da0 25 }
jsa1969 0:cef60cc92da0 26
jsa1969 44:67a19da5f269 27 int I2cCallbacks::read(const uint8_t address, uint8_t *buffer, const uint16_t length, int lock){
jsa1969 44:67a19da5f269 28 if (buffer == NULL || length <= 0 || lock!=_currentlock)
jsa1969 2:544117df8c65 29 return MICROBIT_INVALID_PARAMETER;
jsa1969 44:67a19da5f269 30
jsa1969 44:67a19da5f269 31 int result = _i2c->read(address, (char *)buffer, length);
jsa1969 42:ce269f988ac8 32
jsa1969 2:544117df8c65 33 if (result !=0)
jsa1969 2:544117df8c65 34 return MICROBIT_I2C_ERROR;
jsa1969 2:544117df8c65 35
jsa1969 2:544117df8c65 36 return MICROBIT_OK;
jsa1969 2:544117df8c65 37 }
jsa1969 2:544117df8c65 38
jsa1969 44:67a19da5f269 39 int I2cCallbacks::write(const uint8_t dev_id, const uint8_t reg_addr, const uint8_t *data, const uint16_t length, int lock){
jsa1969 44:67a19da5f269 40 if (lock!=_currentlock)
jsa1969 44:67a19da5f269 41 return MICROBIT_INVALID_PARAMETER;
jsa1969 44:67a19da5f269 42
jsa1969 2:544117df8c65 43 char tmpBuf[length+1];
jsa1969 0:cef60cc92da0 44 tmpBuf[0] = reg_addr;
jsa1969 0:cef60cc92da0 45 for (int i=0,j=1; i <length ; ++i,++j){
jsa1969 0:cef60cc92da0 46 tmpBuf[j] = data[i];
jsa1969 0:cef60cc92da0 47 }
jsa1969 0:cef60cc92da0 48
jsa1969 44:67a19da5f269 49 return _i2c->write(dev_id, tmpBuf, length+1);
jsa1969 0:cef60cc92da0 50 }
jsa1969 0:cef60cc92da0 51
jsa1969 44:67a19da5f269 52 int I2cCallbacks::write(const uint8_t dev_id, const uint8_t *data, const uint16_t length, int lock){
jsa1969 44:67a19da5f269 53 if (lock!=_currentlock)
jsa1969 44:67a19da5f269 54 return MICROBIT_INVALID_PARAMETER;
jsa1969 44:67a19da5f269 55
jsa1969 44:67a19da5f269 56 return _i2c->write(dev_id, (char*)data, length);
jsa1969 42:ce269f988ac8 57 }
jsa1969 42:ce269f988ac8 58
jsa1969 42:ce269f988ac8 59 void I2cCallbacks::delay_ms_relaxed(const uint32_t period) {
jsa1969 42:ce269f988ac8 60 _uBit->sleep(period);
jsa1969 2:544117df8c65 61 }
jsa1969 2:544117df8c65 62
jsa1969 42:ce269f988ac8 63 void I2cCallbacks::delay_ms_strict(const uint32_t period) {
jsa1969 44:67a19da5f269 64 delay_ms_relaxed(period);
jsa1969 44:67a19da5f269 65 /*
jsa1969 42:ce269f988ac8 66 unsigned long endTime = _uBit->systemTime() + period;
jsa1969 42:ce269f988ac8 67 while (_uBit->systemTime() < endTime) {
jsa1969 44:67a19da5f269 68 }*/
jsa1969 0:cef60cc92da0 69 }
jsa1969 42:ce269f988ac8 70
jsa1969 44:67a19da5f269 71 int I2cCallbacks::acquireLock() {
jsa1969 44:67a19da5f269 72 while (_currentlock!=0) _uBit->sleep(1);
jsa1969 44:67a19da5f269 73 _currentlock = _uBit->random(9999999);
jsa1969 44:67a19da5f269 74 }
jsa1969 44:67a19da5f269 75
jsa1969 44:67a19da5f269 76 void I2cCallbacks::releaseLock() {
jsa1969 44:67a19da5f269 77 _currentlock = 0;
jsa1969 42:ce269f988ac8 78 }