The LTR-308ALS-SYM is an integrated low voltage I2C ambient light sensor (ALS) in a single 2x2mm miniature chipled lead-free surface mount package. The ALS provides a linear response over a wide dynamic range, which is well suited to applications under very low or bright ambient brightness. The sensor has a programmable interrupt with hysteresis to response to events and that removes the need to poll the sensor for a reading which improves system efficiency. This CMOS design and factory-set one time trimming capability ensure minimal sensor-to-sensor variations for ease of manufacturability to the end customers.
Obtain ambient light source data, which can be converted to lux according to the raw data obtained. To set the interrupt, you can set the upper and lower limit of the light source, and set the upper and lower value boundary to trigger several times, the interrupt is triggered.
First download the library file, paste it into the \Arduino\libraries directory, then open the examples folder and run the demo in that folder.
/**
* @fn begin
* @brief Initialize the function.
* @return bool ,Indicates the initialization state.
*/
bool begin(void);
/**
* @fn setPowerUp
* @brief Set the Power Up LTR308.
*/
void setPowerUp(void);
/**
* @fn setPowerDown
* @brief Set the Power Down LTR308
*/
void setPowerDown(void);
/**
* @fn getPower
* @brief Get the Power value
* @return uint8_t: content of LTR308_CONTR control register
*/
uint8_t getPower(void);
/**
* @fn setGain
* @brief Set the Gain of LTR308
* @param gain eGain_t
* @n eGain_1X device is set to 1X gain
* @n eGain_3X device is set to 3X gain (Sensor default)
* @n eGain_6X device is set to 6X gain
* @n eGain_9X device is set to 9X gain
* @n eGain_18X device is set to 18X gain
*/
void setGain(eGain_t gain);
/**
* @fn getGain
* @brief Get the Gain of LTR308
* @return uint8_t: the control register values
* @retval 0 device is set to 1X gain
* @retval 1 device is set to 3X gain (Sensor default)
* @retval 2 device is set to 6X gain
* @retval 3 device is set to 9X gain
* @retval 4 device is set to 18X gain
*/
uint8_t getGain(void);
/**
* @fn setMeasurementRate
* @brief Set the Measurement Rate and resolution
* @param measRate: (sMeasRate_t) Measurement Rate and resolution
* @n measRate.resolution (eResolution_t)
* @n eConversion_400ms_20b 20 Bit result, Conversion time = 400ms.
* @n eConversion_200ms_19b 19 Bit result, Conversion time = 200ms.
* @n eConversion_100ms_18b 18 Bit result, Conversion time = 100ms.(Sensor default)
* @n eConversion_50ms_17b 17 Bit result, Conversion time = 50ms.
* @n eConversion_25ms_16b 16 Bit result, Conversion time = 25ms.
* @n -------------------------------------------------------------------------------------------
* @n measRate.measurementRate (eMeasurementRate_t)
* @n eRate_25ms Measurement Rate will be 25ms.
* @n eRate_50ms Measurement Rate will be 50ms.
* @n eRate_100ms Measurement Rate will be 100ms.(Sensor default)
* @n eRate_500ms Measurement Rate will be 500ms.
* @n eRate_1000ms Measurement Rate will be 1000ms.
* @n eRate_2000ms Measurement Rate will be 2000ms.
* @n eRate_2000ms_2 Measurement Rate will be 2000ms.
*/
void setMeasurementRate(sMeasRate_t measRate);
/**
* @fn setMeasurementRate
* @brief Set the Measurement Rate and resolution
* @param resolution: (eResolution_t) The measurement time for each ALs cycle
* @n eConversion_400ms_20b 20 Bit result, Conversion time = 400ms.
* @n eConversion_200ms_19b 19 Bit result, Conversion time = 200ms.
* @n eConversion_100ms_18b 18 Bit result, Conversion time = 100ms.(Sensor default)
* @n eConversion_50ms_17b 17 Bit result, Conversion time = 50ms.
* @n eConversion_25ms_16b 16 Bit result, Conversion time = 25ms.
* @param measurementRate: (eMeasurementRate_t) The interval between DATA_REGISTERS update
* @n eRate_25ms Measurement Rate will be 25ms.
* @n eRate_50ms Measurement Rate will be 50ms.
* @n eRate_100ms Measurement Rate will be 100ms.(Sensor default)
* @n eRate_500ms Measurement Rate will be 500ms.
* @n eRate_1000ms Measurement Rate will be 1000ms.
* @n eRate_2000ms Measurement Rate will be 2000ms.
* @n eRate_2000ms_2 Measurement Rate will be 2000ms.
*/
void setMeasurementRate(eResolution_t resolution, eMeasurementRate_t measurementRate);
/**
* @fn getMeasurementRate
* @brief Get the Measurement Rate and resolution
* @return sMeasRate_t: Measurement Rate and resolution
* @retval sMeasRate_t.resolution (eResolution_t)
* @retval 0 20 Bit result, Conversion time = 400ms.
* @retval 1 19 Bit result, Conversion time = 200ms.
* @retval 2 18 Bit result, Conversion time = 100ms.(Sensor default)
* @retval 3 17 Bit result, Conversion time = 50ms.
* @retval 4 16 Bit result, Conversion time = 25ms.
* @retval -------------------------------------------------------------------------------------------
* @retval sMeasRate_t.measurementRate (eMeasurementRate_t)
* @retval 0 Measurement Rate will be 25ms.
* @retval 1 Measurement Rate will be 50ms.
* @retval 2 Measurement Rate will be 100ms.(Sensor default)
* @retval 3 Measurement Rate will be 500ms.
* @retval 5 Measurement Rate will be 1000ms.
* @retval 6 Measurement Rate will be 2000ms.
* @retval 7 Measurement Rate will be 2000ms.
*/
sMeasRate_t getMeasurementRate(void);
/**
* @fn getPartID
* @brief Gets the part number ID and revision ID of the chip
* @return uint8_t: Default value is 0xB1, part number ID = 0xB, revision ID = 0x1.
*/
uint8_t getPartID(void);
/**
* @fn getStatus
* @brief Get the Status of LTR308
* @return sMainStatus_t: The status information of LTR308.
* @retval If sMainStatus_t.ponStatus = false(0), power on event (default)
* @retval If sMainStatus_t.ponStatus = true(1), not specified in datasheet
* @retval -------------------------------------------------------------------------------------------
* @retval If sMainStatus_t.intrStatus = false(0), Interrupt is NOT triggered (default)
* @retval If sMainStatus_t.intrStatus = true(1), Interrupt is triggered and will be cleared after read
* @retval -------------------------------------------------------------------------------------------
* @retval If sMainStatus_t.dataStatus = false(0), ALS data is old (Data has been read)
* @retval If sMainStatus_t.dataStatus = true(1), ALS data is new data (Data has not been read and will be cleared after read)
*/
sMainStatus_t getStatus(void);
/**
* @fn getData
* @brief Get the ALS channel data
* @return uint32_t: ALS data, Default value is 0
*/
uint32_t getData(void);
/**
* @fn setInterruptControl
* @brief Set the Interrupt Control of LTR308
* @param mode: interrupt mode
* @n If mode = false(0), ALS interrupt disabled (default)
* @n If mdoe = true(1), ALS interrupt enabled
*/
void setInterruptControl(bool mode);
/**
* @fn getInterruptControl
* @brief Get the Interrupt Control of LTR308
* @return bool: interrupt mode
* @retval true: ALS interrupt enabled
* @retval false: ALS interrupt disabled
*/
bool getInterruptControl(void);
/**
* @fn setIntrPersist
* @brief Set the Intr Persist of LTR308
* @param persist: controls the N number of times the measurement data is outside the range defined by upper and lower threshold
* @n eInterruptTrigger_1 Every ALS value out of threshold range asserts an interrupt (default)
* @n eInterruptTrigger_2 2 consecutive ALS values out of threshold range assert an interrupt
* @n eInterruptTrigger_3 3 consecutive ALS values out of threshold range assert an interrupt
* @n eInterruptTrigger_4 4 consecutive ALS values out of threshold range assert an interrupt
* @n eInterruptTrigger_5 5 consecutive ALS values out of threshold range assert an interrupt
* @n eInterruptTrigger_6 6 consecutive ALS values out of threshold range assert an interrupt
* @n eInterruptTrigger_7 7 consecutive ALS values out of threshold range assert an interrupt
* @n eInterruptTrigger_8 8 consecutive ALS values out of threshold range assert an interrupt
* @n eInterruptTrigger_9 9 consecutive ALS values out of threshold range assert an interrupt
* @n eInterruptTrigger_10 10 consecutive ALS values out of threshold range assert an interrupt
* @n eInterruptTrigger_11 11 consecutive ALS values out of threshold range assert an interrupt
* @n eInterruptTrigger_12 12 consecutive ALS values out of threshold range assert an interrupt
* @n eInterruptTrigger_13 13 consecutive ALS values out of threshold range assert an interrupt
* @n eInterruptTrigger_14 14 consecutive ALS values out of threshold range assert an interrupt
* @n eInterruptTrigger_15 15 consecutive ALS values out of threshold range assert an interrupt
* @n eInterruptTrigger_16 16 consecutive ALS values out of threshold range assert an interrupt
*/
void setIntrPersist(eIntrPersist_t persist);
/**
* @fn getIntrPersist
* @brief Get the Intr Persist of LTR308
* @return uint8_t: controls the N number of times the measurement data is outside the range defined by upper and lower threshold
* @retval 0 Every ALS value out of threshold range asserts an interrupt (default)
* @retval 1 2 consecutive ALS values out of threshold range assert an interrupt
* @retval 2 3 consecutive ALS values out of threshold range assert an interrupt
* @retval 3 4 consecutive ALS values out of threshold range assert an interrupt
* @retval 4 5 consecutive ALS values out of threshold range assert an interrupt
* @retval 5 6 consecutive ALS values out of threshold range assert an interrupt
* @retval 6 7 consecutive ALS values out of threshold range assert an interrupt
* @retval 7 8 consecutive ALS values out of threshold range assert an interrupt
* @retval 8 9 consecutive ALS values out of threshold range assert an interrupt
* @retval 9 10 consecutive ALS values out of threshold range assert an interrupt
* @retval 10 11 consecutive ALS values out of threshold range assert an interrupt
* @retval 11 12 consecutive ALS values out of threshold range assert an interrupt
* @retval 12 13 consecutive ALS values out of threshold range assert an interrupt
* @retval 13 14 consecutive ALS values out of threshold range assert an interrupt
* @retval 14 15 consecutive ALS values out of threshold range assert an interrupt
* @retval 15 16 consecutive ALS values out of threshold range assert an interrupt
*/
uint8_t getIntrPersist(void);
/**
* @fn setThreshold
* @brief Sets the upper limit and lower limit of the threshold
* @param thres: upperLimit and lowerLimit
* @n thres.upperLimit (up to 20-bits) (default 0x0FFFFF)
* @n thres.lowerLimit (up to 20-bits) (default 0x000000)
*/
void setThreshold(sThres_t thres);
/**
* @fn setThreshold
* @brief Sets the upper limit and lower limit of the threshold
* @param upperLimit: (up to 20-bits) (default 0x0FFFFF)
* @param lowerLimit: (up to 20-bits) (default 0x000000)
*/
void setThreshold(uint32_t upperLimit, uint32_t lowerLimit);
/**
* @fn getThreshold
* @brief Gets the upper limit and lower limit of the threshold
* @return sThres_t: upperLimit and lowerLimit
* @retval sThres_t.upperLimit (up to 20-bits) (default 0x0FFFFF)
* @retval sThres_t.lowerLimit (up to 20-bits) (default 0x000000)
*/
sThres_t getThreshold();
/**
* @fn getLux
* @brief Convert raw data to lux (Lux = (0.6 * ALSDATA) / (GAIN * INT))
* @param gain: The gain of this sensor
* @param resolution: The resolution of this sensor
* @param alsData: The ALS Data of this sensor
* @return double: The converted lux value
*/
double getLux(eGain_t gain, eResolution_t resolution, uint32_t alsData);
/**
* @fn getLux
* @brief Convert raw data to lux (Lux = (0.6 * ALSDATA) / (GAIN * INT))
* @param alsData: The ALS Data of this sensor
* @return double: The converted lux value
*/
double getLux(uint32_t alsData);
| MCU | Work Well | Work Wrong | Untested | Remarks |
|---|---|---|---|---|
| Arduino Uno | √ | |||
| Arduino MEGA2560 | √ | |||
| Arduino Leonardo | √ | |||
| ESP8266 | √ | |||
| ESP32 | √ | |||
| FireBeetle-M0 | √ | |||
| Micro:bit | √ |
- 2024/07/30 - V1.0.0 version
Written by thdyyl([email protected]), 2024. (Welcome to our website)