AOSong AM2315 topic

Quick Notes

• Applies to both the AOSong AM2315 and CM2311 capacitive relative humidity and temperature sensors
• Depends on the Adafruit AM2315 Library.
• Communicates via I2C
  • only one address possible, 0xB8
• Only 1 can be connected to a single I2C bus at a time
• Requires a 3.3 - 5.5V power source

Sensor Datasheet

Datasheet

Sensor Constructors

Example Code

The AM2315 is used in the double logger and menu a la carte example

Classes

class AOSongAM2315

The Sensor sub-class for the AOSong AM2315.

class AOSongAM2315_Humidity

The Variable sub-class used for the relative humidity output from an AOSong AM2315.

class AOSongAM2315_Temp

The Variable sub-class used for the temperature output from an AOSong AM2315.

Sensor Variable Counts

The number of variables that can be returned by an AOSong AM2315

#define AM2315_NUM_VARIABLES = 2

Sensor::_numReturnedValues; the AM2315 can report 2 values.

#define AM2315_INC_CALC_VARIABLES = 0

Sensor::_incCalcValues; we don't calculate any additional values.

Sensor Timing

The sensor timing for an AOSong AM2315

#define AM2315_WARM_UP_TIME_MS = 500

Sensor::_warmUpTime_ms; the AM2315 warms up in 500ms (estimated).

#define AM2315_STABILIZATION_TIME_MS = 500

Sensor::_stabilizationTime_ms; the AM2315 is stable after 500ms (estimated).

#define AM2315_MEASUREMENT_TIME_MS = 2000

Sensor::_measurementTime_ms; the AM2315 takes 2000ms (2s) to complete a measurement.

Humidity

The humidity variable from an AOSong AM2315

• Range is 0 to 100% RH
• Accuracy is ± 2 % RH at 25°C

#define AM2315_HUMIDITY_RESOLUTION = 1

Decimals places in string representation; humidity should have 1 (0.1 % RH for the 16 bit sensor).

#define AM2315_HUMIDITY_VAR_NUM = 0

Sensor variable number; humidity is stored in sensorValues[0].

#define AM2315_HUMIDITY_VAR_NAME = "relativeHumidity"

Variable name in ODM2 controlled vocabulary; "relativeHumidity".

#define AM2315_HUMIDITY_UNIT_NAME = "percent"

Variable unit name in ODM2 controlled vocabulary; "percent" (percent relative humidity)

#define AM2315_HUMIDITY_DEFAULT_CODE = "AM2315Humidity"

Default variable short code; "AM2315Humidity".

Temperature

The temperature variable from an AOSong AM2315

• Range is -40°C to +125°C
• Accuracy is ±0.1°C

#define AM2315_TEMP_RESOLUTION = 1

Decimals places in string representation; temperature should have 1. (0.1°C for the 16 bit sensor)

#define AM2315_TEMP_VAR_NUM = 1

Sensor variable number; temperature is stored in sensorValues[1].

#define AM2315_TEMP_VAR_NAME = "temperature"

Variable name in ODM2 controlled vocabulary; "temperature".

#define AM2315_TEMP_UNIT_NAME = "degreeCelsius"

Variable unit name in ODM2 controlled vocabulary; "degreeCelsius" (°C)

#define AM2315_TEMP_DEFAULT_CODE = "AM2315Temp"

Default variable short code; "AM2315Temp".

Define documentation