API Reference¶

SHT3x¶

Sht3xI2cDevice¶

class sensirion_i2c_sht.sht3x.device.Sht3xI2cDevice(connection, slave_address=68)[source]¶

SHT3x I²C device class to allow executing I²C commands.

__init__(connection, slave_address=68)[source]¶

Constructs a new SHT3x I²C device.

Parameters:	connection (I2cConnection) – The I²C connection to use for communication. slave_address (byte) – The I²C slave address, defaults to 0x44.

single_shot_measurement(repeatability=<Sht3xRepeatability.HIGH: 1>)[source]¶

Trigger a measurement and read the temperature and humidity.

Parameters:	repeatability (Sht3xRepeatability) – Configure the repeatability setting.
Raises:	ValueError – If the passed repeatability is not valid.
Returns:	The measured temperature and humidity. temperature (`Sht3xTemperature`) - Temperature response object. humidity (`Sht3xHumidity`) - Humidity response object.
Return type:	tuple

art_enable()[source]¶: Enable the ART (accelerated response time

heater_on()[source]¶: Switch on the internal heater.

heater_off()[source]¶: Switch off the internal heater.

read_status_register()[source]¶

Read out the status register.

Returns:	The status register.
Return type:	`Sht3xStatusRegister`

clear_status_register()[source]¶: Clear the status register. All flags (Bit 15, 11, 10, 4) in the status register can be cleared (set to zero).

soft_reset()[source]¶: Perform a soft reset for the device. This can be used to force the system into a well-defined state without removing the power supply.

read_serial_number()[source]¶

Read the serial number from the device.

Returns:	The serial number.
Return type:	int

connection¶

Get the used I²C connection.

Returns:	The used I²C connection.
Return type:	I2cConnection

execute(command)¶

Execute an I²C command on this device.

Parameters:	command (I2cCommand) – The command to be executed.
Returns:	The interpreted response of the executed command.
Return type:	Depends on the executed command.

slave_address¶

Get the I²C slave address.

Returns:	The I²C slave address.
Return type:	byte

Sht3xI2cCommand¶

class sensirion_i2c_sht.sht3x.commands.Sht3xI2cCmdBase(command, tx_data, rx_length, read_delay, timeout, post_processing_time=0.0)[source]¶

SHT3x I²C base command.

__init__(command, tx_data, rx_length, read_delay, timeout, post_processing_time=0.0)[source]¶

Constructs a new SHT3x I²C command.

Parameters:

command (int/None) – The command ID to be sent to the device. None means that no command will be sent, i.e. only tx_data (if not None) will be sent. No CRC is added to these bytes since the command ID usually already contains a CRC.
tx_data (bytes-like/list/None) – Bytes to be extended with CRCs and then sent to the I²C device. None means that no write header will be sent at all (if command is None too). An empty list means to send the write header (even if command is None), but without data following it.
rx_length (int/None) – Number of bytes to be read from the I²C device, including CRC bytes. None means that no read header is sent at all. Zero means to send the read header, but without reading any data.
read_delay (float) – Delay (in Seconds) to be inserted between the end of the write operation and the beginning of the read operation. This is needed if the device needs some time to prepare the RX data, e.g. if it has to perform a measurement. Set to 0.0 to indicate that no delay is needed, i.e. the device does not need any processing time.
timeout (float) – Timeout (in Seconds) to be used in case of clock stretching. If the device stretches the clock longer than this value, the transceive operation will be aborted with a timeout error. Set to 0.0 to indicate that the device will not stretch the clock for this command.
post_processing_time (float) – Maximum time in seconds the device needs for post processing of this command until it is ready to receive the next command. For example after a device reset command, the device might need some time until it is ready again. Usually this is 0.0s, i.e. no post processing is needed.

interpret_response(data)¶

Validates the CRCs of the received data from the device and returns the data with all CRCs removed.

Parameters:	data (bytes) – Received raw bytes from the read operation.
Returns:	The received bytes, or None if there is no data received.
Return type:	bytes or None
Raises:	I2cChecksumError – If a received CRC was wrong.

class sensirion_i2c_sht.sht3x.commands.Sht3xI2cCmdMeasBase(command, read_delay)[source]¶

Base SHT3x command for a single shot measurement with clock stretching disabled.

__init__(command, read_delay)[source]¶

Constructs a new command.

Parameters:

command (int/None) – The command word to be sent to the device. None means that no command will be sent, i.e. only tx_words (if not None) will be sent.
read_delay (float) – Delay (in Seconds) to be inserted between the end of the write operation and the beginning of the read operation. This is needed if the device needs some time to prepare the RX data, e.g. if it has to perform a measurement. Set to 0.0 to indicate that no delay is needed, i.e. the device does not need any processing time.

interpret_response(data)[source]¶

Converts the raw response from the device to the proper data type.

Parameters:	data (bytes) – Received raw bytes from the read operation.
Returns:	The measured temperature and humidity. temperature (`Sht3xTemperature`) - Temperature response object. humidity (`Sht3xHumidity`) - Humidity response object.
Return type:	tuple

class sensirion_i2c_sht.sht3x.commands.Sht3xI2cCmdMeasHighRes[source]¶

SHT3x command for a single shot measurement with high repeatability and clock stretching disabled.

__init__()[source]¶: Constructs a new command.

interpret_response(data)¶

Converts the raw response from the device to the proper data type.

Parameters:	data (bytes) – Received raw bytes from the read operation.
Returns:	The measured temperature and humidity. temperature (`Sht3xTemperature`) - Temperature response object. humidity (`Sht3xHumidity`) - Humidity response object.
Return type:	tuple

class sensirion_i2c_sht.sht3x.commands.Sht3xI2cCmdMeasMediumRes[source]¶

SHT3x command for a single shot measurement with medium repeatability and clock stretching disabled.

__init__()[source]¶: Constructs a new command.

interpret_response(data)¶

Converts the raw response from the device to the proper data type.

Parameters:	data (bytes) – Received raw bytes from the read operation.
Returns:	The measured temperature and humidity. temperature (`Sht3xTemperature`) - Temperature response object. humidity (`Sht3xHumidity`) - Humidity response object.
Return type:	tuple

class sensirion_i2c_sht.sht3x.commands.Sht3xI2cCmdMeasLowRes[source]¶

SHT3x command for a single shot measurement with low repeatability and clock stretching disabled.

__init__()[source]¶: Constructs a new command.

interpret_response(data)¶

Converts the raw response from the device to the proper data type.

Parameters:	data (bytes) – Received raw bytes from the read operation.
Returns:	The measured temperature and humidity. temperature (`Sht3xTemperature`) - Temperature response object. humidity (`Sht3xHumidity`) - Humidity response object.
Return type:	tuple

class sensirion_i2c_sht.sht3x.commands.Sht3xI2cCmdEnableART[source]¶

SHT3x command to enable the ART (accelerated response time) feature.

__init__()[source]¶: Constructs a new command.

interpret_response(data)¶

Validates the CRCs of the received data from the device and returns the data with all CRCs removed.

Parameters:	data (bytes) – Received raw bytes from the read operation.
Returns:	The received bytes, or None if there is no data received.
Return type:	bytes or None
Raises:	I2cChecksumError – If a received CRC was wrong.

class sensirion_i2c_sht.sht3x.commands.Sht3xI2cCmdHeaterOn[source]¶

SHT3x command to enable the internal heater.

__init__()[source]¶: Constructs a new command.

interpret_response(data)¶

Validates the CRCs of the received data from the device and returns the data with all CRCs removed.

Parameters:	data (bytes) – Received raw bytes from the read operation.
Returns:	The received bytes, or None if there is no data received.
Return type:	bytes or None
Raises:	I2cChecksumError – If a received CRC was wrong.

class sensirion_i2c_sht.sht3x.commands.Sht3xI2cCmdHeaterOff[source]¶

SHT3x command to disable the internal heater.

__init__()[source]¶: Constructs a new command.

interpret_response(data)¶

Validates the CRCs of the received data from the device and returns the data with all CRCs removed.

Parameters:	data (bytes) – Received raw bytes from the read operation.
Returns:	The received bytes, or None if there is no data received.
Return type:	bytes or None
Raises:	I2cChecksumError – If a received CRC was wrong.

class sensirion_i2c_sht.sht3x.commands.Sht3xI2cCmdSoftReset[source]¶

SHT3x command for a soft reset.

__init__()[source]¶: Constructs a new command.

interpret_response(data)¶

Validates the CRCs of the received data from the device and returns the data with all CRCs removed.

Parameters:	data (bytes) – Received raw bytes from the read operation.
Returns:	The received bytes, or None if there is no data received.
Return type:	bytes or None
Raises:	I2cChecksumError – If a received CRC was wrong.

class sensirion_i2c_sht.sht3x.commands.Sht3xI2cCmdReadStatusRegister[source]¶

SHT3x command to read the status register.

__init__()[source]¶: Constructs a new command.

interpret_response(data)[source]¶

Converts the raw response from the device to the proper data type.

Parameters:	data (bytes) – Received raw bytes from the read operation.
Returns:	The status register.
Return type:	`Sht3xStatusRegister`

class sensirion_i2c_sht.sht3x.commands.Sht3xI2cCmdResetStatusRegister[source]¶

SHT3x command to reset the status register.

__init__()[source]¶: Constructs a new command.

interpret_response(data)¶

Validates the CRCs of the received data from the device and returns the data with all CRCs removed.

Parameters:	data (bytes) – Received raw bytes from the read operation.
Returns:	The received bytes, or None if there is no data received.
Return type:	bytes or None
Raises:	I2cChecksumError – If a received CRC was wrong.

class sensirion_i2c_sht.sht3x.commands.Sht3xI2cCmdReadSerial[source]¶

SHT3x command to read the serial number.

__init__()[source]¶: Constructs a new command.

interpret_response(data)[source]¶

Converts the raw response from the device to the proper data type.

Parameters:	data (bytes) – Received raw bytes from the read operation.
Returns:	The serial number.
Return type:	int

Data Types¶

class sensirion_i2c_sht.sht3x.data_types.Sht3xRepeatability[source]¶

An enum containing all available repeatability settings for the temperature and humidity measurement.

HIGH = 1¶: High repeatability

MEDIUM = 2¶: Medium repeatability

LOW = 3¶: Low repeatability

Response Types¶

class sensirion_i2c_sht.sht3x.response_types.Sht3xTemperature(ticks)[source]¶

Represents a measurement response for the temperature.

With the ticks you can access the raw data as received from the device. For the converted values you can choose between degrees_celsius and degrees_fahrenheit.

Parameters:	ticks (int) – The read ticks as received from the device.

__init__(ticks)[source]¶: Creates an instance from the received raw data.

ticks¶: The ticks (int) as received from the device.

degrees_celsius¶: The converted temperature in °C.

degrees_fahrenheit¶: The converted temperature in °F.

class sensirion_i2c_sht.sht3x.response_types.Sht3xHumidity(ticks)[source]¶

Represents a measurement response for the humidity.

With the ticks you can access the raw data as received from the device. For the converted value the percent_rh attribute is available.

Parameters:	ticks (int) – The read ticks as received from the device.

__init__(ticks)[source]¶: Creates an instance from the received raw data.

ticks¶: The ticks (int) as received from the device.

percent_rh¶: The converted humidity in %RH.

class sensirion_i2c_sht.sht3x.response_types.Sht3xStatusRegister(raw)[source]¶

Represents the content of the status register.

With the status_register_word you can access the raw data as received from the device. For each data field of the status register an attribute is available.

Parameters:	raw (int) – The read status register word as received from the device.

__init__(raw)[source]¶: Creates an instance from the received raw data.

raw¶: The raw data word (int) as received from the device.

write_data_checksum_status¶

Write data checksum status (Bit 0, bool)

False: checksum of last write transfer was correct
True: checksum of last write transfer failed

command_status¶

Command status (Bit 1, bool)

False: last command executed successfully
True: last command not processed. It was either invalid or failed the integrated command checksum

temperature_tracking_alert¶

Temperature tracking alert (Bit 10, bool)

False: no alert
True: alert

humidity_tracking_alert¶

Humidity tracking alert (Bit 11, bool)

False: no alert
True: alert

heater_status¶

Heater status (Bit 13, bool)

False: heater off
True: heater on

alert_pending_status¶

Alert pending status (Bit 15, bool)

False: no pending alerts
True: at least one pending alert