GY-63_MS5611/libraries/MAX44007/README.md
2023-10-04 10:40:31 +02:00

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License: MIT GitHub release PlatformIO Registry

Max44007 I2C LUX sensor

Library for Max44007 I2C lux sensor.

Description

The Max44007 ambient light sensor is an I2C sensor, that has a 22 bit dynamic range from 0.025 lux to 104,448 lux.

This library is experimental and created by changing some key values in the very similar MAX44009 library. As there was no hardware available the library is not tested yet. If you do, please share the results (open an issue on GitHub).

Note: version 0.2.0 simplified the constructor interface and removed configure().

Schema breakout Max44007

//      breakout Max44007
//
//          +--------+
//      VCC |o       |
//      GND |o       |
//      SCL |o      o| ADDRESS
//      SDA |o      o| -INT
//          +--------+
//
//  ADDRESS:
//  0 = 0x5A
//  1 = 0x5B
//
//  INT:
//  Connect the INT pin to an pull up resistor
//  0 = interrupt
//  1 = no interrupt
//  connect to an LED or an interrupt pin of an Arduino
//

Interface

#include "Max44007.h"

Constructor

  • Max44007(const uint8_t address = MAX44007_DEFAULT_ADDRESS, TwoWire *wire = &Wire) Constructor. Optional address and optional I2C interface.\
  • bool isConnected() returns true if the device address configured is available on I2C bus.

NOTE: The user must call Wire.begin() or Wire.begin(SDA, SCL) in setup().

Basic

  • float getLux() read the sensor and return the value in LUX. If the value is negative, an error has occurred.
  • int getError() returns last error.
//  ERROR CODES
#define Max44007_OK                     0
#define Max44007_ERROR_WIRE_REQUEST    -10
#define Max44007_ERROR_OVERFLOW        -20
#define Max44007_ERROR_HIGH_BYTE       -30
#define Max44007_ERROR_LOW_BYTE        -31

Configure thresholds

check datasheet for details

  • bool setHighThreshold(float value) sets the upper threshold for the interrupt generation (INT pulls LOW). Works only if INTE bit is set by enableInterrupt(). Function returns false if the value is out of range.
  • float getHighThreshold() returns the value set.
  • bool setLowThreshold(float value) sets the lower threshold for the interrupt generation (INT pulls LOW). Works only if INTE bit is set by enableInterrupt(). Function returns false if the value is out of range.
  • float getLowThreshold() returns the value set.
  • void setThresholdTimer(uint8_t value) Time the threshold needs to be exceeded, defined in steps of 100ms. 2 seems to be a practical minimum.
  • uint8_t getThresholdTimer() returns the value set.

Configure interrupts

check datasheet for details

  • void enableInterrupt() enables the upper and lower threshold interrupts.
  • void disableInterrupt() disables the threshold interrupts.
  • bool interruptEnabled() returns 1 if the interrupt mode is enabled.
  • uint8_t getInterruptStatus() returns 1 if an interrupt has occurred.

Configure flags

check datasheet for details

  • void setConfiguration(uint8_t) writes directly to configuration register. warning Use with care.
  • uint8_t getConfiguration() reads the current configuration register.

Configure sample mode

Check datasheet for details

CCR = Current Divisor Ratio.

TIM = Integration time.

  • void setAutomaticMode() in automatic mode the Max44007 determines the CDR and TIM parameters.
  • void setContinuousMode() continuous mode uses more power than a "single" conversion. Advantage is that the latest data is always available fast.
  • void clrContinuousMode() uses less power so better for LOW power configurations.
  • void setManualMode(uint8_t CDR, uint8_t TIM) Set the Current Divisor Ratio and the integration time manually. Effectively disable automatic mode.
  • int getIntegrationTime() returns the set integration time in milliseconds
    CDR = Current Divisor Ratio
    CDR = 1 ==> only 1/8th is measured

    TIM = Time Integration Measurement (table)
    000   800ms
    001   400ms
    010   200ms
    011   100ms
    100    50ms       manual only
    101    25ms       manual only
    110    12.5ms     manual only
    111     6.25ms    manual only

Test functions

Function for the conversion math, not meant to be used directly, but by making them public they become testable.

  • float convertToLux(uint8_t dataHigh, uint8_t dataLow) convert intern register format to a LUX value.

Examples

Max44007\examples\Max44007_test01

  • use for e.g. UNO (use voltage convertor!)

Max44007\examples\Max44007_test02

  • will not compile for UNO
  • use for e.g. ESP32

Notes

Please be aware this is a 3.3 Volt device so it should not be connected to an Arduino UNO or other 5 Volt device directly. Use a level convertor to solve this.

Do not forget to connect the address pin as you cannot read the sensor in a reliable way. As the line will float it will sometimes have the right address and sometimes not. (been there ;)

Pull ups on I2C bus are recommended.

Future

Must

  • follow MAX44009

Should

Could

  • merge MAX44007 / MAX44009 library in the future. (shared base class?)

Wont

Support

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Thank you,