// -----------------------------------------------------------------------------
|
|
// BME280/BMP280 Sensor over I2C
|
|
// Copyright (C) 2017-2018 by Xose Pérez <xose dot perez at gmail dot com>
|
|
// -----------------------------------------------------------------------------
|
|
|
|
#if SENSOR_SUPPORT && BMX280_SUPPORT
|
|
|
|
#pragma once
|
|
|
|
#include "Arduino.h"
|
|
#include "I2CSensor.h"
|
|
|
|
#define BMX280_CHIP_BMP280 0x58
|
|
#define BMX280_CHIP_BME280 0x60
|
|
|
|
#define BMX280_REGISTER_DIG_T1 0x88
|
|
#define BMX280_REGISTER_DIG_T2 0x8A
|
|
#define BMX280_REGISTER_DIG_T3 0x8C
|
|
|
|
#define BMX280_REGISTER_DIG_P1 0x8E
|
|
#define BMX280_REGISTER_DIG_P2 0x90
|
|
#define BMX280_REGISTER_DIG_P3 0x92
|
|
#define BMX280_REGISTER_DIG_P4 0x94
|
|
#define BMX280_REGISTER_DIG_P5 0x96
|
|
#define BMX280_REGISTER_DIG_P6 0x98
|
|
#define BMX280_REGISTER_DIG_P7 0x9A
|
|
#define BMX280_REGISTER_DIG_P8 0x9C
|
|
#define BMX280_REGISTER_DIG_P9 0x9E
|
|
|
|
#define BMX280_REGISTER_DIG_H1 0xA1
|
|
#define BMX280_REGISTER_DIG_H2 0xE1
|
|
#define BMX280_REGISTER_DIG_H3 0xE3
|
|
#define BMX280_REGISTER_DIG_H4 0xE4
|
|
#define BMX280_REGISTER_DIG_H5 0xE5
|
|
#define BMX280_REGISTER_DIG_H6 0xE7
|
|
|
|
#define BMX280_REGISTER_CHIPID 0xD0
|
|
#define BMX280_REGISTER_VERSION 0xD1
|
|
#define BMX280_REGISTER_SOFTRESET 0xE0
|
|
|
|
#define BMX280_REGISTER_CAL26 0xE1
|
|
|
|
#define BMX280_REGISTER_CONTROLHUMID 0xF2
|
|
#define BMX280_REGISTER_CONTROL 0xF4
|
|
#define BMX280_REGISTER_CONFIG 0xF5
|
|
#define BMX280_REGISTER_PRESSUREDATA 0xF7
|
|
#define BMX280_REGISTER_TEMPDATA 0xFA
|
|
#define BMX280_REGISTER_HUMIDDATA 0xFD
|
|
|
|
class BMX280Sensor : public I2CSensor {
|
|
|
|
public:
|
|
|
|
static unsigned char addresses[2];
|
|
|
|
// ---------------------------------------------------------------------
|
|
// Public
|
|
// ---------------------------------------------------------------------
|
|
|
|
BMX280Sensor(): I2CSensor() {
|
|
_sensor_id = SENSOR_BMX280_ID;
|
|
}
|
|
|
|
// ---------------------------------------------------------------------
|
|
// Sensor API
|
|
// ---------------------------------------------------------------------
|
|
|
|
// Initialization method, must be idempotent
|
|
void begin() {
|
|
|
|
if (!_dirty) return;
|
|
_dirty = false;
|
|
_chip = 0;
|
|
|
|
// I2C auto-discover
|
|
_address = _begin_i2c(_address, sizeof(BMX280Sensor::addresses), BMX280Sensor::addresses);
|
|
if (_address == 0) return;
|
|
|
|
// Init
|
|
_init();
|
|
|
|
}
|
|
|
|
// Descriptive name of the sensor
|
|
String description() {
|
|
char buffer[20];
|
|
snprintf(buffer, sizeof(buffer), "%s @ I2C (0x%02X)", _chip == BMX280_CHIP_BME280 ? "BME280" : "BMP280", _address);
|
|
return String(buffer);
|
|
}
|
|
|
|
// Type for slot # index
|
|
unsigned char type(unsigned char index) {
|
|
unsigned char i = 0;
|
|
#if BMX280_TEMPERATURE > 0
|
|
if (index == i++) return MAGNITUDE_TEMPERATURE;
|
|
#endif
|
|
#if BMX280_PRESSURE > 0
|
|
if (index == i++) return MAGNITUDE_PRESSURE;
|
|
#endif
|
|
#if BMX280_HUMIDITY > 0
|
|
if (_chip == BMX280_CHIP_BME280) {
|
|
if (index == i) return MAGNITUDE_HUMIDITY;
|
|
}
|
|
#endif
|
|
return MAGNITUDE_NONE;
|
|
}
|
|
|
|
// Pre-read hook (usually to populate registers with up-to-date data)
|
|
virtual void pre() {
|
|
|
|
if (_chip == 0) {
|
|
_error = SENSOR_ERROR_UNKNOWN_ID;
|
|
return;
|
|
}
|
|
_error = SENSOR_ERROR_OK;
|
|
|
|
#if BMX280_MODE == 1
|
|
_forceRead();
|
|
#endif
|
|
_read();
|
|
|
|
}
|
|
|
|
// Current value for slot # index
|
|
double value(unsigned char index) {
|
|
unsigned char i = 0;
|
|
#if BMX280_TEMPERATURE > 0
|
|
if (index == i++) return _temperature;
|
|
#endif
|
|
#if BMX280_PRESSURE > 0
|
|
if (index == i++) return _pressure / 100;
|
|
#endif
|
|
#if BMX280_HUMIDITY > 0
|
|
if (_chip == BMX280_CHIP_BME280) {
|
|
if (index == i) return _humidity;
|
|
}
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
// Load the configuration manifest
|
|
static void manifest(JsonArray& sensors) {
|
|
|
|
char buffer[10];
|
|
|
|
JsonObject& sensor = sensors.createNestedObject();
|
|
sensor["sensor_id"] = SENSOR_BMX280_ID;
|
|
JsonArray& fields = sensor.createNestedArray("fields");
|
|
|
|
{
|
|
JsonObject& field = fields.createNestedObject();
|
|
field["tag"] = UI_TAG_SELECT;
|
|
field["name"] = "address";
|
|
field["label"] = "Address";
|
|
JsonArray& options = field.createNestedArray("options");
|
|
{
|
|
JsonObject& option = options.createNestedObject();
|
|
option["name"] = "auto";
|
|
option["value"] = 0;
|
|
}
|
|
for (unsigned char i=0; i< sizeof(BMX280Sensor::addresses); i++) {
|
|
JsonObject& option = options.createNestedObject();
|
|
snprintf(buffer, sizeof(buffer), "0x%02X", BMX280Sensor::addresses[i]);
|
|
option["name"] = String(buffer);
|
|
option["value"] = BMX280Sensor::addresses[i];
|
|
}
|
|
}
|
|
|
|
};
|
|
|
|
void getConfig(JsonObject& root) {
|
|
root["sensor_id"] = _sensor_id;
|
|
root["address"] = _address;
|
|
};
|
|
|
|
void setConfig(JsonObject& root) {
|
|
if (root.containsKey("address")) setAddress(root["address"]);
|
|
};
|
|
|
|
protected:
|
|
|
|
void _init() {
|
|
|
|
// Make sure sensor had enough time to turn on. BMX280 requires 2ms to start up
|
|
delay(10);
|
|
|
|
// Check sensor correctly initialized
|
|
_chip = i2c_read_uint8(_address, BMX280_REGISTER_CHIPID);
|
|
if ((_chip != BMX280_CHIP_BME280) && (_chip != BMX280_CHIP_BMP280)) {
|
|
_chip = 0;
|
|
i2cReleaseLock(_address);
|
|
_error = SENSOR_ERROR_UNKNOWN_ID;
|
|
}
|
|
|
|
#if BMX280_TEMPERATURE > 0
|
|
++_count;
|
|
#endif
|
|
#if BMX280_PRESSURE > 0
|
|
++_count;
|
|
#endif
|
|
#if BMX280_HUMIDITY > 0
|
|
if (_chip == BMX280_CHIP_BME280) ++_count;
|
|
#endif
|
|
|
|
_readCoefficients();
|
|
|
|
unsigned char data = 0;
|
|
i2c_write_uint8(_address, BMX280_REGISTER_CONTROL, data);
|
|
|
|
data = (BMX280_STANDBY << 0x5) & 0xE0;
|
|
data |= (BMX280_FILTER << 0x02) & 0x1C;
|
|
i2c_write_uint8(_address, BMX280_REGISTER_CONFIG, data);
|
|
|
|
data = (BMX280_HUMIDITY) & 0x07;
|
|
i2c_write_uint8(_address, BMX280_REGISTER_CONTROLHUMID, data);
|
|
|
|
data = (BMX280_TEMPERATURE << 5) & 0xE0;
|
|
data |= (BMX280_PRESSURE << 2) & 0x1C;
|
|
data |= (BMX280_MODE) & 0x03;
|
|
i2c_write_uint8(_address, BMX280_REGISTER_CONTROL, data);
|
|
|
|
_measurement_delay = _measurementTime();
|
|
|
|
}
|
|
|
|
void _readCoefficients() {
|
|
_bmx280_calib.dig_T1 = i2c_read_uint16_le(_address, BMX280_REGISTER_DIG_T1);
|
|
_bmx280_calib.dig_T2 = i2c_read_int16_le(_address, BMX280_REGISTER_DIG_T2);
|
|
_bmx280_calib.dig_T3 = i2c_read_int16_le(_address, BMX280_REGISTER_DIG_T3);
|
|
|
|
_bmx280_calib.dig_P1 = i2c_read_uint16_le(_address, BMX280_REGISTER_DIG_P1);
|
|
_bmx280_calib.dig_P2 = i2c_read_int16_le(_address, BMX280_REGISTER_DIG_P2);
|
|
_bmx280_calib.dig_P3 = i2c_read_int16_le(_address, BMX280_REGISTER_DIG_P3);
|
|
_bmx280_calib.dig_P4 = i2c_read_int16_le(_address, BMX280_REGISTER_DIG_P4);
|
|
_bmx280_calib.dig_P5 = i2c_read_int16_le(_address, BMX280_REGISTER_DIG_P5);
|
|
_bmx280_calib.dig_P6 = i2c_read_int16_le(_address, BMX280_REGISTER_DIG_P6);
|
|
_bmx280_calib.dig_P7 = i2c_read_int16_le(_address, BMX280_REGISTER_DIG_P7);
|
|
_bmx280_calib.dig_P8 = i2c_read_int16_le(_address, BMX280_REGISTER_DIG_P8);
|
|
_bmx280_calib.dig_P9 = i2c_read_int16_le(_address, BMX280_REGISTER_DIG_P9);
|
|
|
|
_bmx280_calib.dig_H1 = i2c_read_uint8(_address, BMX280_REGISTER_DIG_H1);
|
|
_bmx280_calib.dig_H2 = i2c_read_int16_le(_address, BMX280_REGISTER_DIG_H2);
|
|
_bmx280_calib.dig_H3 = i2c_read_uint8(_address, BMX280_REGISTER_DIG_H3);
|
|
_bmx280_calib.dig_H4 = (i2c_read_uint8(_address, BMX280_REGISTER_DIG_H4) << 4) | (i2c_read_uint8(_address, BMX280_REGISTER_DIG_H4+1) & 0xF);
|
|
_bmx280_calib.dig_H5 = (i2c_read_uint8(_address, BMX280_REGISTER_DIG_H5+1) << 4) | (i2c_read_uint8(_address, BMX280_REGISTER_DIG_H5) >> 4);
|
|
_bmx280_calib.dig_H6 = (int8_t) i2c_read_uint8(_address, BMX280_REGISTER_DIG_H6);
|
|
}
|
|
|
|
unsigned long _measurementTime() {
|
|
|
|
// Measurement Time (as per BMX280 datasheet section 9.1)
|
|
// T_max(ms) = 1.25
|
|
// + (2.3 * T_oversampling)
|
|
// + (2.3 * P_oversampling + 0.575)
|
|
// + (2.4 * H_oversampling + 0.575)
|
|
// ~ 9.3ms for current settings
|
|
|
|
double t = 1.25;
|
|
#if BMX280_TEMPERATURE > 0
|
|
t += (2.3 * BMX280_TEMPERATURE);
|
|
#endif
|
|
#if BMX280_PRESSURE > 0
|
|
t += (2.3 * BMX280_PRESSURE + 0.575);
|
|
#endif
|
|
#if BMX280_HUMIDITY > 0
|
|
if (_chip == BMX280_CHIP_BME280) {
|
|
t += (2.4 * BMX280_HUMIDITY + 0.575);
|
|
}
|
|
#endif
|
|
|
|
return round(t + 1); // round up
|
|
|
|
}
|
|
|
|
void _forceRead() {
|
|
|
|
// We set the sensor in "forced mode" to force a reading.
|
|
// After the reading the sensor will go back to sleep mode.
|
|
uint8_t value = i2c_read_uint8(_address, BMX280_REGISTER_CONTROL);
|
|
value = (value & 0xFC) + 0x01;
|
|
i2c_write_uint8(_address, BMX280_REGISTER_CONTROL, value);
|
|
|
|
delay(_measurement_delay);
|
|
|
|
}
|
|
|
|
void _read() {
|
|
|
|
#if BMX280_TEMPERATURE > 0
|
|
int32_t adc_T = i2c_read_uint16(_address, BMX280_REGISTER_TEMPDATA);
|
|
adc_T <<= 8;
|
|
adc_T |= i2c_read_uint8(_address, BMX280_REGISTER_TEMPDATA+2);
|
|
adc_T >>= 4;
|
|
|
|
int32_t var1t = ((((adc_T>>3) -
|
|
((int32_t)_bmx280_calib.dig_T1 <<1))) *
|
|
((int32_t)_bmx280_calib.dig_T2)) >> 11;
|
|
|
|
int32_t var2t = (((((adc_T>>4) -
|
|
((int32_t)_bmx280_calib.dig_T1)) *
|
|
((adc_T>>4) - ((int32_t)_bmx280_calib.dig_T1))) >> 12) *
|
|
((int32_t)_bmx280_calib.dig_T3)) >> 14;
|
|
|
|
int32_t t_fine = var1t + var2t;
|
|
|
|
double T = (t_fine * 5 + 128) >> 8;
|
|
_temperature = T / 100;
|
|
#else
|
|
int32_t t_fine = 102374; // ~20ºC
|
|
#endif
|
|
|
|
// -----------------------------------------------------------------
|
|
|
|
#if BMX280_PRESSURE > 0
|
|
int64_t var1, var2, p;
|
|
|
|
int32_t adc_P = i2c_read_uint16(_address, BMX280_REGISTER_PRESSUREDATA);
|
|
adc_P <<= 8;
|
|
adc_P |= i2c_read_uint8(_address, BMX280_REGISTER_PRESSUREDATA+2);
|
|
adc_P >>= 4;
|
|
|
|
var1 = ((int64_t)t_fine) - 128000;
|
|
var2 = var1 * var1 * (int64_t)_bmx280_calib.dig_P6;
|
|
var2 = var2 + ((var1*(int64_t)_bmx280_calib.dig_P5)<<17);
|
|
var2 = var2 + (((int64_t)_bmx280_calib.dig_P4)<<35);
|
|
var1 = ((var1 * var1 * (int64_t)_bmx280_calib.dig_P3)>>8) +
|
|
((var1 * (int64_t)_bmx280_calib.dig_P2)<<12);
|
|
var1 = (((((int64_t)1)<<47)+var1))*((int64_t)_bmx280_calib.dig_P1)>>33;
|
|
if (var1 == 0) return; // avoid exception caused by division by zero
|
|
|
|
p = 1048576 - adc_P;
|
|
p = (((p<<31) - var2)*3125) / var1;
|
|
var1 = (((int64_t)_bmx280_calib.dig_P9) * (p>>13) * (p>>13)) >> 25;
|
|
var2 = (((int64_t)_bmx280_calib.dig_P8) * p) >> 19;
|
|
|
|
p = ((p + var1 + var2) >> 8) + (((int64_t)_bmx280_calib.dig_P7)<<4);
|
|
_pressure = (double) p / 256;
|
|
#endif
|
|
|
|
// -----------------------------------------------------------------
|
|
|
|
#if BMX280_HUMIDITY > 0
|
|
if (_chip == BMX280_CHIP_BME280) {
|
|
|
|
int32_t adc_H = i2c_read_uint16(_address, BMX280_REGISTER_HUMIDDATA);
|
|
|
|
int32_t v_x1_u32r;
|
|
|
|
v_x1_u32r = (t_fine - ((int32_t)76800));
|
|
|
|
v_x1_u32r = (((((adc_H << 14) - (((int32_t)_bmx280_calib.dig_H4) << 20) -
|
|
(((int32_t)_bmx280_calib.dig_H5) * v_x1_u32r)) + ((int32_t)16384)) >> 15) *
|
|
(((((((v_x1_u32r * ((int32_t)_bmx280_calib.dig_H6)) >> 10) *
|
|
(((v_x1_u32r * ((int32_t)_bmx280_calib.dig_H3)) >> 11) + ((int32_t)32768))) >> 10) +
|
|
((int32_t)2097152)) * ((int32_t)_bmx280_calib.dig_H2) + 8192) >> 14));
|
|
|
|
v_x1_u32r = (v_x1_u32r - (((((v_x1_u32r >> 15) * (v_x1_u32r >> 15)) >> 7) *
|
|
((int32_t)_bmx280_calib.dig_H1)) >> 4));
|
|
|
|
v_x1_u32r = (v_x1_u32r < 0) ? 0 : v_x1_u32r;
|
|
v_x1_u32r = (v_x1_u32r > 419430400) ? 419430400 : v_x1_u32r;
|
|
double h = (v_x1_u32r >> 12);
|
|
_humidity = h / 1024.0;
|
|
|
|
}
|
|
#endif
|
|
|
|
}
|
|
|
|
// ---------------------------------------------------------------------
|
|
|
|
unsigned char _chip;
|
|
unsigned long _measurement_delay;
|
|
double _temperature = 0;
|
|
double _pressure = 0;
|
|
double _humidity = 0;
|
|
|
|
typedef struct {
|
|
|
|
uint16_t dig_T1;
|
|
int16_t dig_T2;
|
|
int16_t dig_T3;
|
|
|
|
uint16_t dig_P1;
|
|
int16_t dig_P2;
|
|
int16_t dig_P3;
|
|
int16_t dig_P4;
|
|
int16_t dig_P5;
|
|
int16_t dig_P6;
|
|
int16_t dig_P7;
|
|
int16_t dig_P8;
|
|
int16_t dig_P9;
|
|
|
|
uint8_t dig_H1;
|
|
int16_t dig_H2;
|
|
uint8_t dig_H3;
|
|
int16_t dig_H4;
|
|
int16_t dig_H5;
|
|
int8_t dig_H6;
|
|
|
|
} bmx280_calib_t;
|
|
|
|
bmx280_calib_t _bmx280_calib;
|
|
|
|
};
|
|
|
|
// Static inizializations
|
|
|
|
unsigned char BMX280Sensor::addresses[2] = {0x76, 0x77};
|
|
|
|
#endif // SENSOR_SUPPORT && BMX280_SUPPORT
|