Old library cannot be compiled well for ESP32 (as declarations are conflicted with ESP SDK declarations), so used again inline-C code for more modern Arduino library:
Module name 'esp_bh1750':
'module name 'esp_bh1750'
'install this Arduino library: https://github.com/claws/BH1750
Private Sub Process_Globals
'These global variables will be declared once when the application starts.
'Public variables can be accessed from all modules.
Dim LightLux As Float
Private Timer1 As Timer
End Sub
Sub Start
Log("Start reading BH1750...")
RunNative("prepare_bh1750", Null)
Timer1.Initialize("Timer1_Tick", 1000)
Timer1.Enabled = True
End Sub
Private Sub Timer1_Tick
RunNative("read_bh1750", Null)
Log(LightLux, " lx")
End Sub
#if C
/*
Advanced BH1750 library usage example
This example has some comments about advanced usage features.
Connections
- VCC to 3V3 or 5V
- GND to GND
- SCL to SCL (A5 on Arduino Uno, Leonardo, etc or 21 on Mega and Due, on
esp8266 free selectable)
- SDA to SDA (A4 on Arduino Uno, Leonardo, etc or 20 on Mega and Due, on
esp8266 free selectable)
- ADD to (not connected) or GND
ADD pin is used to set sensor I2C address. If it has voltage greater or equal
to 0.7VCC voltage (e.g. you've connected it to VCC) the sensor address will be
0x5C. In other case (if ADD voltage less than 0.7 * VCC) the sensor address
will be 0x23 (by default).
*/
#include <BH1750.h>
#include <Wire.h>
/*
BH1750 can be physically configured to use two I2C addresses:
- 0x23 (most common) (if ADD pin had < 0.7VCC voltage)
- 0x5C (if ADD pin had > 0.7VCC voltage)
Library uses 0x23 address as default, but you can define any other address.
If you had troubles with default value - try to change it to 0x5C.
*/
BH1750 lightMeter(0x23);
void prepare_bh1750(B4R::Object* o) {
// Initialize the I2C bus (BH1750 library doesn't do this automatically)
Wire.begin();
// On esp8266 you can select SCL and SDA pins using Wire.begin(D4, D3);
/*
BH1750 has six different measurement modes. They are divided in two groups;
continuous and one-time measurements. In continuous mode, sensor
continuously measures lightness value. In one-time mode the sensor makes
only one measurement and then goes into Power Down mode.
Each mode, has three different precisions:
- Low Resolution Mode - (4 lx precision, 16ms measurement time)
- High Resolution Mode - (1 lx precision, 120ms measurement time)
- High Resolution Mode 2 - (0.5 lx precision, 120ms measurement time)
By default, the library uses Continuous High Resolution Mode, but you can
set any other mode, by passing it to BH1750.begin() or BH1750.configure()
functions.
[!] Remember, if you use One-Time mode, your sensor will go to Power Down
mode each time, when it completes a measurement and you've read it.
Full mode list:
BH1750_CONTINUOUS_LOW_RES_MODE
BH1750_CONTINUOUS_HIGH_RES_MODE (default)
BH1750_CONTINUOUS_HIGH_RES_MODE_2
BH1750_ONE_TIME_LOW_RES_MODE
BH1750_ONE_TIME_HIGH_RES_MODE
BH1750_ONE_TIME_HIGH_RES_MODE_2
*/
// begin returns a boolean that can be used to detect setup problems.
if (lightMeter.begin(BH1750::CONTINUOUS_HIGH_RES_MODE)) {
//Serial.println(F("BH1750 Advanced begin"));
} else {
Serial.println(F("Error initialising BH1750"));
}
}
void read_bh1750(B4R::Object* o) {
if (lightMeter.measurementReady()) {
float lux = lightMeter.readLightLevel();
b4r_esp_bh1750::_lightlux = lux;
// Serial.print("Light: ");
// Serial.print(lux);
// Serial.println(" lx");
}
}
#End If
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