ModularSensors > Modules > Supported Sensors > Atlas Scientific EZO Circuits > Atlas EZO-DO

Atlas EZO-DO module

Classes for the Atlas Scientific EZO-DO dissolved oxygen circuit and probe.

The Atlas Scientifc DO sensor outputs DO in both mg/L and percent saturation.

Sensor Datasheet

Documentation on the probe is found here: https://www.atlas-scientific.com/probes/dissolved-oxygen-probe/

Documentation on the measurement circuit is found here: https://www.atlas-scientific.com/circuits/ezo-dissolved-oxygen-circuit/

Sensor Constructors

AtlasScientificDO(int8_t powerPin, uint8_t i2cAddressHex = ATLAS_DO_I2C_ADDR, uint8_t measurementsToAverage = 1) explicit

Construct a new Atlas Scientific DO object using the primary hardware I2C instance.

Parameters
powerPin

The pin on the mcu controlling powering to the Atlas DO circuit. Use -1 if it is continuously powered.

  • Requires a 3.3V and 5V power supply
i2cAddressHex The I2C address of the Atlas circuit; optional with the Atlas-supplied default address of 0x61.
measurementsToAverage The number of measurements to take and average before giving a "final" result from the sensor; optional with a default value of 1.

AtlasScientificDO(TwoWire* theI2C, int8_t powerPin, uint8_t i2cAddressHex = ATLAS_DO_I2C_ADDR, uint8_t measurementsToAverage = 1)

Construct a new Atlas Scientific DO object using a secondary hardware I2C instance.

Parameters
theI2C A TwoWire instance for I2C communication. Due to the limitations of the Arduino core, only a hardware I2C instance can be used. For an AVR board, there is only one I2C instance possible and this form of the constructor should not be used. For a SAMD board, this can be used if a secondary I2C port is created on one of the extra SERCOMs.
powerPin

The pin on the mcu controlling powering to the Atlas DO circuit. Use -1 if it is continuously powered.

  • Requires a 3.3V and 5V power supply
i2cAddressHex The I2C address of the Atlas circuit; optional with the Atlas-supplied default address of 0x61.
measurementsToAverage The number of measurements to take and average before giving a "final" result from the sensor; optional with a default value of 1.


Example Code

The Atlas DO sensor is used in the menu a la carte example.

#include <sensors/AtlasScientificDO.h>

const int8_t AtlasDOPower    = sensorPowerPin;  // Power pin (-1 if unconnected)
uint8_t      AtlasDOi2c_addr = 0x61;            // Default for DO is 0x61 (97)
// All Atlas sensors have different default I2C addresses, but any of them can
// be re-addressed to any 8 bit number.  If using the default address for any
// Atlas Scientific sensor, you may omit this argument.

// Create an Atlas Scientific DO sensor object
// AtlasScientificDO atlasDO(AtlasDOPower, AtlasDOi2c_addr);
AtlasScientificDO atlasDO(AtlasDOPower);

// Create concentration and percent saturation variable pointers for the EZO-DO
Variable* atlasDOconc = new AtlasScientificDO_DOmgL(
    &atlasDO, "12345678-abcd-1234-ef00-1234567890ab");
Variable* atlasDOpct = new AtlasScientificDO_DOpct(
    &atlasDO, "12345678-abcd-1234-ef00-1234567890ab");

Classes

class AtlasScientificDO
The Sensor sub-class for the Atlas Scientific EZO dissolved oxygen circuit.
class AtlasScientificDO_DOmgL
The Variable sub-class used for the dissolved oxygen concentration output from an Atlas Scientific EZO dissolved oxygen circuit.
class AtlasScientificDO_DOpct
The Variable sub-class used for the dissolved oxygen percent of saturation output from an Atlas Scientific EZO dissolved oxygen circuit.

Defines

#define ATLAS_DO_NUM_VARIABLES = 2
Sensor::_numReturnedValues; the Atlas DO sensor can report 2 values.

Sensor Timing

The sensor timing for an Atlas DO sensor

#define ATLAS_DO_WARM_UP_TIME_MS = 745
Sensor::_warmUpTime_ms; the Atlas DO sensor warms up in 745ms.

737-739 in tests

#define ATLAS_DO_STABILIZATION_TIME_MS = 0
Sensor::_stabilizationTime_ms; the Atlas DO sensor is stable at completion of warm up (0ms after warm-up).
#define ATLAS_DO_MEASUREMENT_TIME_MS = 600
Sensor::_measurementTime_ms; the Atlas DO sensor takes 600ms to complete a measurement.

only ~555 measurement time in tests, but keep the 600 recommended by manual

DO Concentration

The dissolved oxygen concentration from an Atlas DO sensor

  • Accuracy is ± 0.05 mg/L
  • Range is 0.01 − 100+ mg/L

AtlasScientificDO_DOmgL(AtlasScientificDO* parentSense, const char* uuid = "", const char* varCode = ATLAS_DOMGL_DEFAULT_CODE) explicit

Construct a new AtlasScientificDO_DOmgL object.

Parameters
parentSense The parent AtlasScientificDO providing the result values.
uuid A universally unique identifier (UUID or GUID) for the variable; optional with the default value of an empty string.
varCode A short code to help identify the variable in files; optional with a default value of "AtlasDOmgL".

#define ATLAS_DOMGL_RESOLUTION = 2
Decimals places in string representation; dissolved oxygen concentration should have 2 - resolution is 0.01 mg/L.
#define ATLAS_DOMGL_VAR_NUM = 0
Sensor variable number; dissolved oxygen concentration is stored in sensorValues[0].
#define ATLAS_DOMGL_VAR_NAME = "oxygenDissolved"
Variable name in ODM2 controlled vocabulary; "oxygenDissolved".
#define ATLAS_DOMGL_UNIT_NAME = "milligramPerLiter"
Variable unit name in ODM2 controlled vocabulary; "milligramPerLiter" (mg/L)
#define ATLAS_DOMGL_DEFAULT_CODE = "AtlasDOmgL"
Default variable short code; "AtlasDOmgL".

DO Percent Saturation

The dissolved oxygen percent saturation for an Atlas DO sensor

  • Accuracy is ± 0.05 mg/L
  • Range is 0.1 − 400+ % saturation

AtlasScientificDO_DOpct(AtlasScientificDO* parentSense, const char* uuid = "", const char* varCode = ATLAS_DOPCT_DEFAULT_CODE) explicit

Construct a new AtlasScientificDO_DOpct object.

Parameters
parentSense The parent AtlasScientificDO providing the result values.
uuid A universally unique identifier (UUID or GUID) for the variable; optional with the default value of an empty string.
varCode A short code to help identify the variable in files; optional with a default value of "AtlasDOpct".

#define ATLAS_DOPCT_RESOLUTION = 1
Decimals places in string representation; dissolved oxygen percent should have 1 - resolution is 0.1 % saturation.
#define ATLAS_DOPCT_VAR_NUM = 1
Sensor variable number; dissolved oxygen percent is stored in sensorValues[1].
#define ATLAS_DOPCT_VAR_NAME = "oxygenDissolvedPercentOfSaturation"
Variable name in ODM2 controlled vocabulary; "oxygenDissolvedPercentOfSaturation".
#define ATLAS_DOPCT_UNIT_NAME = "percent"
Variable unit name in ODM2 controlled vocabulary; "percent" (percent saturation)
#define ATLAS_DOPCT_DEFAULT_CODE = "AtlasDOpct"
Default variable short code; "AtlasDOpct".