API Reference

SHT2x

Sht2xI2cDevice

class sensirion_i2c_sht.sht2x.device.Sht2xI2cDevice(connection, slave_address=64)

SHT2x I²C device class to allow executing I²C commands.

__init__(connection, slave_address=64)

Constructs a new SHT2x 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()

Trigger a measurement and read the temperature and humidity.

Returns:The measured temperature and humidity.

• temperature (Sht2xTemperature) - Temperature response object.
• humidity (Sht2xHumidity) - Humidity response object.

Return type:tuple

soft_reset()

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()

Read the extended serial number from the device.

Returns:The extended 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

Sht2xI2cCommand

class sensirion_i2c_sht.sht2x.commands.Sht2xI2cCmdBase(command, tx_data, rx_length, read_delay, timeout, command_bytes=1, post_processing_time=0.0)

Sht2x I²C base command.

__init__(command, tx_data, rx_length, read_delay, timeout, command_bytes=1, post_processing_time=0.0)

Constructs a new SHT2x 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.
• command_bytes (int) – Number of command bytes.
• 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.sht2x.commands.Sht2xI2cMeasureHumidity

Sht2x command for a single shot measurement with clock stretching disabled.

__init__()

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 read humidity. Return type:Sht2xHumidity

class sensirion_i2c_sht.sht2x.commands.Sht2xI2cMeasureTemperature

Sht2x command for a single shot measurement with clock stretching disabled.

__init__()

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 read temperature. Return type:Sht2xTemperature

class sensirion_i2c_sht.sht2x.commands.Sht2xI2cCmdSoftReset

Sht2x command for a soft reset.

__init__()

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.sht2x.commands.Sht2xI2cCmdReadOtp(address, number_of_bytes_to_read)

Sht2x command to read from the OTP.

__init__(address, number_of_bytes_to_read)

Constructs a new command.

Parameters:

• address (byte) – Address of OTP to read from.
• number_of_bytes_to_read (int) – Number of bytes to read.

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 read bytes from the OTP. Return type:list(int)

class sensirion_i2c_sht.sht2x.commands.Sht2xI2cCmdReadMetalRom(number_of_words_to_read)

Sht2x command to read from the metal ROM.

__init__(number_of_words_to_read)

Constructs a new command.

Parameters:number_of_words_to_read (int) – Number of words to read.

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 read words from the metal ROM. Return type:list(int)

Response Types

class sensirion_i2c_sht.sht2x.response_types.Sht2xTemperature(ticks)

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)

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.sht2x.response_types.Sht2xHumidity(ticks)

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)

Creates an instance from the received raw data.

ticks

The ticks (int) as received from the device.

percent_rh

The converted humidity in %RH.

SHT3x

Sht3xI2cDevice

class sensirion_i2c_sht.sht3x.device.Sht3xI2cDevice(connection, slave_address=68)

SHT3x I²C device class to allow executing I²C commands.

__init__(connection, slave_address=68)

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>)

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()

Enable the ART (accelerated response time

heater_on()

Switch on the internal heater.

heater_off()

Switch off the internal heater.

read_status_register()

Read out the status register.

Returns:The status register. Return type:Sht3xStatusRegister

clear_status_register()

Clear the status register. All flags (Bit 15, 11, 10, 4) in the status register can be cleared (set to zero).

soft_reset()

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()

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)

SHT3x I²C base command.

__init__(command, tx_data, rx_length, read_delay, timeout, post_processing_time=0.0)

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)

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

__init__(command, read_delay)

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)

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

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

__init__()

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

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

__init__()

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

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

__init__()

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

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

__init__()

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

SHT3x command to enable the internal heater.

__init__()

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

SHT3x command to disable the internal heater.

__init__()

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

SHT3x command for a soft reset.

__init__()

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

SHT3x command to read the status register.

__init__()

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 status register. Return type:Sht3xStatusRegister

class sensirion_i2c_sht.sht3x.commands.Sht3xI2cCmdResetStatusRegister

SHT3x command to reset the status register.

__init__()

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

SHT3x command to read the serial number.

__init__()

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 serial number. Return type:int

Data Types

class sensirion_i2c_sht.sht3x.data_types.Sht3xRepeatability

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)

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)

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)

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)

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)

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)

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

SHTC3

Shtc3I2cDevice

class sensirion_i2c_sht.shtc3.device.Shtc3I2cDevice(connection, slave_address=112)

SHTC3 I²C device class to allow executing I²C commands.

__init__(connection, slave_address=112)

Constructs a new SHTC3 I²C device.

Parameters:

• connection (I2cConnection) – The I²C connection to use for communication.
• slave_address (byte) – The I²C slave address, defaults to 0x70.

measure(power_mode=<Shtc3PowerMode.NORMAL: 2>)

Trigger a measurement with clock stretching disabled and read the temperature and humidity.

Parameters:power_mode (Shtc3PowerMode) – Configure the power mode setting. Raises:ValueError – If the passed power mode is not valid. Returns:The measured temperature and humidity.

• temperature (Shtc3xTemperature) - Temperature response object.
• humidity (Shtc3Humidity) - Humidity response object.

Return type:tuple

measure_clock_stretching(power_mode=<Shtc3PowerMode.NORMAL: 2>)

Trigger a measurement with clock stretching enabled and read the temperature and humidity.

Parameters:power_mode (Shtc3PowerMode) – Configure the power mode setting. Raises:ValueError – If the passed power mode is not valid. Returns:The measured temperature and humidity.

• temperature (Shtc3xTemperature) - Temperature response object.
• humidity (Shtc3Humidity) - Humidity response object.

Return type:tuple

read_product_id()

Read the product id from the device.

Returns:The product id. Return type:int

wake_up()

wake up SHTC3.

Note

When the sensor is in sleep mode, it requires the wake-up command before any further communication

enter_sleep()

Sleep command of the sensor.

Note

Upon VDD reaching the power-up voltage level V_POR , the SHTC3 enters the idle state after a duration of 240us. After that, the sensor should be set to sleep.

soft_reset()

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.

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

Shtc3I2cCommand

class sensirion_i2c_sht.shtc3.commands.Shtc3I2cCmdBase(command, tx_data, rx_length, read_delay, timeout, post_processing_time=0.0)

shtc3 I²C base command.

__init__(command, tx_data, rx_length, read_delay, timeout, post_processing_time=0.0)

Constructs a new shtc3 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.shtc3.commands.Shtc3I2cCmdMeasureNormalModeTicksClockStretching

Measure Normal Mode Ticks Clock Stretching I²C Command

Measure in normal mode with clock stretching enabled.

__init__()

Constructor.

interpret_response(data)

Validates the CRCs of the received data from the device and returns the interpreted data.

Parameters:data (bytes) – Received raw bytes from the read operation. Returns:

• temperature (Shtc3xTemperature) - Temperature response object.
• humidity (Shtc3Humidity) - Humidity response object.

Return type:tuple Raises:I2cChecksumError – If a received CRC was wrong.

class sensirion_i2c_sht.shtc3.commands.Shtc3I2cCmdMeasureLowestPowerModeTicksClockStretching

Measure Lowest Power Mode Ticks Clock Stretching I²C Command

Measure in low power mode with clock stretching enabled.

__init__()

Constructor.

interpret_response(data)

Validates the CRCs of the received data from the device and returns the interpreted data.

Parameters:data (bytes) – Received raw bytes from the read operation. Returns:

• temperature (Shtc3xTemperature) - Temperature response object.
• humidity (Shtc3Humidity) - Humidity response object.

Return type:tuple Raises:I2cChecksumError – If a received CRC was wrong.

class sensirion_i2c_sht.shtc3.commands.Shtc3I2cCmdMeasureNormalModeTicks

Measure Normal Mode Ticks I²C Command

Measure in normal mode with clock stretching disabled.

__init__()

Constructor.

interpret_response(data)

Validates the CRCs of the received data from the device and returns the interpreted data.

Parameters:data (bytes) – Received raw bytes from the read operation. Returns:

• temperature (Shtc3xTemperature) - Temperature response object.
• humidity (Shtc3Humidity) - Humidity response object.

Return type:tuple Raises:I2cChecksumError – If a received CRC was wrong.

class sensirion_i2c_sht.shtc3.commands.Shtc3I2cCmdMeasureLowestPowerModeTicks

Measure Lowest Power Mode Ticks I²C Command

Measure in low power mode with clock stretching disabled.

__init__()

Constructor.

interpret_response(data)

Validates the CRCs of the received data from the device and returns the interpreted data.

Parameters:data (bytes) – Received raw bytes from the read operation. Returns:

• temperature (Shtc3xTemperature) - Temperature response object.
• humidity (Shtc3Humidity) - Humidity response object.

Return type:tuple Raises:I2cChecksumError – If a received CRC was wrong.

class sensirion_i2c_sht.shtc3.commands.Shtc3I2cCmdProductId

Product Id I²C Command

Read out the product id.

Note

The SHTC3 has an ID register which contains an SHTC3- specific product code. The read-out of the ID register can be used to verify the presence of the sensor and proper communication.

__init__()

Constructor.

interpret_response(data)

Validates the CRCs of the received data from the device and returns the interpreted data.

Parameters:data (bytes) – Received raw bytes from the read operation. Returns:SHTC3-specific product code Return type:int Raises:I2cChecksumError – If a received CRC was wrong.

class sensirion_i2c_sht.shtc3.commands.Shtc3I2cCmdSoftReset

Soft Reset I²C Command

Perform a soft reset. reset all internal state machines and reload calibration data from the memory.

Note

A reset of the sensor can be achieved in three ways: • Soft reset: use this function • I2C general call: all devices on the I2C bus are reset by sending the command 0x06 to the I2C address 0x00. • Power down (incl.pulling SCL and SDA low)

__init__()

Constructor.

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.shtc3.commands.Shtc3I2cCmdWakeUp

Wake Up I²C Command

Wake-up command of the sensor.

Note

When the sensor is in sleep mode, it requires the wake-up command before any further communication

__init__()

Constructor.

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.shtc3.commands.Shtc3I2cCmdSleep

Sleep I²C Command

Sleep command of the sensor.

Note

Upon VDD reaching the power-up voltage level V_POR , the SHTC3 enters the idle state after a duration of 240us. After that, the sensor should be set to sleep.

__init__()

Constructor.

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.

Data Types

class sensirion_i2c_sht.shtc3.data_types.Shtc3PowerMode

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

LOW = 1

Low power mode

NORMAL = 2

Normal power mode

Response Types

class sensirion_i2c_sht.shtc3.response_types.Shtc3Temperature(ticks)

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)

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.shtc3.response_types.Shtc3Humidity(ticks)

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)

Creates an instance from the received raw data.

ticks

The ticks (int) as received from the device.

percent_rh

The converted humidity in %RH.

SHT4x

Sht4xI2cDevice

class sensirion_i2c_sht.sht4x.device.Sht4xI2cDevice(connection, slave_address=68)

SHT4x I²C device class to allow executing I²C commands.

__init__(connection, slave_address=68)

Constructs a new SHT4x 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=<Sht4xRepeatability.HIGH: 1>)

Trigger a measurement and read the temperature and humidity.

Parameters:repeatability (Sht4xRepeatability) – Configure the repeatability setting. Raises:ValueError – If the passed repeatability is not valid. Returns:The measured temperature and humidity.

• temperature (Sht4xTemperature) - Temperature response object.
• humidity (Sht4xHumidity) - Humidity response object.

Return type:tuple

activate_heater(power=<Sht4xHeaterPower.HIGH: 1>, duration=<Sht4xHeaterActivationDuration.LONG: 1>)

Activate the heater and trigger a high precision measurement.

Important notes for operating the heater:

• The heater is designed for a maximum duty cycle of 5%.
• During operation of the heater, sensor specifications are not valid.
• The temperature sensor can additionally be affected by the thermally induced mechanical stress, offsetting the temperature reading from the actual temperature.
• The sensor’s temperature (base temperature + temperature increase from heater) must not exceed Tmax = 125 °C in order to have proper electrical functionality of the chip.

If higher heating temperatures are desired, consecutive heating commands have to be sent to the sensor. The heater shall only be operated in ambient temperatures below 65°C else it could drive the sensor outside of its maximal operating temperature.

Parameters:

• power (Sht4xHeaterPower) – Configure the heater power setting.
• duration (Sht4xHeaterActivationDuration) – Configure the heater activation duration.

Raises:

ValueError – If the passed parameters are not valid.

Returns:

The measured temperature and humidity.

• temperature (Sht4xTemperature) - Temperature response object.
• humidity (Sht4xHumidity) - Humidity response object.

Return type:

tuple

soft_reset()

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()

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

Sht4xI2cCommand

class sensirion_i2c_sht.sht4x.commands.Sht4xI2cCmdBase(command, tx_data, rx_length, read_delay, post_processing_time=0.0)

SHT4x I²C base command.

__init__(command, tx_data, rx_length, read_delay, post_processing_time=0.0)

Constructs a new SHT4x 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.
• 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.sht4x.commands.Sht4xI2cCmdMeasBase(command, read_delay)

Base SHT4x command for a single shot measurement.

__init__(command, read_delay)

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)

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 (Sht4xTemperature) - Temperature response object.
• humidity (Sht4xHumidity) - Humidity response object.

Return type:tuple

class sensirion_i2c_sht.sht4x.commands.Sht4xI2cCmdMeasHighRes

SHT4x command for a single shot measurement with high repeatability.

__init__()

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 (Sht4xTemperature) - Temperature response object.
• humidity (Sht4xHumidity) - Humidity response object.

Return type:tuple

class sensirion_i2c_sht.sht4x.commands.Sht4xI2cCmdMeasMediumRes

SHT4x command for a single shot measurement with medium repeatability.

__init__()

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 (Sht4xTemperature) - Temperature response object.
• humidity (Sht4xHumidity) - Humidity response object.

Return type:tuple

class sensirion_i2c_sht.sht4x.commands.Sht4xI2cCmdMeasLowRes

SHT4x command for a single shot measurement with low repeatability.

__init__()

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 (Sht4xTemperature) - Temperature response object.
• humidity (Sht4xHumidity) - Humidity response object.

Return type:tuple

class sensirion_i2c_sht.sht4x.commands.Sht4xI2cCmdHeaterHighPowerLong

SHT4x command activate highest heater power and a high precision measurement (typ. 200mW @ 3.3V) for 1 second.

__init__()

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 (Sht4xTemperature) - Temperature response object.
• humidity (Sht4xHumidity) - Humidity response object.

Return type:tuple

class sensirion_i2c_sht.sht4x.commands.Sht4xI2cCmdHeaterHighPowerShort

SHT4x command activate highest heater power and a high precision measurement (typ. 200mW @ 3.3V) for 0.1 second.

__init__()

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 (Sht4xTemperature) - Temperature response object.
• humidity (Sht4xHumidity) - Humidity response object.

Return type:tuple

class sensirion_i2c_sht.sht4x.commands.Sht4xI2cCmdHeaterMediumPowerLong

SHT4x command activate medium heater power and a high precision measurement (typ. 110mW @ 3.3V) for 1 second.

__init__()

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 (Sht4xTemperature) - Temperature response object.
• humidity (Sht4xHumidity) - Humidity response object.

Return type:tuple

class sensirion_i2c_sht.sht4x.commands.Sht4xI2cCmdHeaterMediumPowerShort

SHT4x command activate medium heater power and a high precision measurement (typ. 110mW @ 3.3V) for 0.1 second.

__init__()

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 (Sht4xTemperature) - Temperature response object.
• humidity (Sht4xHumidity) - Humidity response object.

Return type:tuple

class sensirion_i2c_sht.sht4x.commands.Sht4xI2cCmdHeaterLowPowerLong

SHT4x command activate lowest heater power and a high precision measurement (typ. 20mW @ 3.3V) for 1 second.

__init__()

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 (Sht4xTemperature) - Temperature response object.
• humidity (Sht4xHumidity) - Humidity response object.

Return type:tuple

class sensirion_i2c_sht.sht4x.commands.Sht4xI2cCmdHeaterLowPowerShort

SHT4x command activate lowest heater power and a high precision measurement (typ. 20mW @ 3.3V) for 0.1 second.

__init__()

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 (Sht4xTemperature) - Temperature response object.
• humidity (Sht4xHumidity) - Humidity response object.

Return type:tuple

class sensirion_i2c_sht.sht4x.commands.Sht4xI2cCmdSoftReset

SHT4x command for a soft reset.

__init__()

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.sht4x.commands.Sht4xI2cCmdReadSerial

SHT4x command to read the serial number.

__init__()

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 serial number. Return type:int

Data Types

class sensirion_i2c_sht.sht4x.data_types.Sht4xRepeatability

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

class sensirion_i2c_sht.sht4x.data_types.Sht4xHeaterPower

An enum containing all available heater power settings.

HIGH = 1

High power (typ. 200mW @ 3.3V)

MEDIUM = 2

Medium power (typ. 110mW @ 3.3V)

LOW = 3

Lowest power (typ. 20mW @ 3.3V)

class sensirion_i2c_sht.sht4x.data_types.Sht4xHeaterActivationDuration

An enum containing all available heater activation duration settings.

LONG = 1

Long duration (typ. 1 second)

SHORT = 2

Short duration (typ. 0.1 seconds)

Response Types

class sensirion_i2c_sht.sht4x.response_types.Sht4xTemperature(ticks)

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)

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.sht4x.response_types.Sht4xHumidity(ticks)

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)

Creates an instance from the received raw data.

ticks

The ticks (int) as received from the device.

percent_rh

The converted humidity in %RH.

STS4x

Sts4xI2cDevice

class sensirion_i2c_sht.sts4x.device.Sts4xI2cDevice(connection, slave_address=68)

STS4x I²C device class to allow executing I²C commands.

__init__(connection, slave_address=68)

Constructs a new STS4x 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=<Sts4xRepeatability.HIGH: 1>)

Trigger a measurement and read the temperature.

Parameters:repeatability (Sts4xRepeatability) – Configure the repeatability setting. Raises:ValueError – If the passed repeatability is not valid. Returns:The measured temperature

• temperature (Sts4xTemperature) - Temperature response object.

Return type:tuple

soft_reset()

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()

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

Sts4xI2cCommand

class sensirion_i2c_sht.sts4x.commands.Sts4xI2cCmdBase(command, tx_data, rx_length, read_delay, post_processing_time=0.0)

STS4x I²C base command.

__init__(command, tx_data, rx_length, read_delay, post_processing_time=0.0)

Constructs a new STS4x 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.
• 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.sts4x.commands.Sts4xI2cCmdMeasBase(command, read_delay)

Base STS4x command for a single shot measurement.

__init__(command, read_delay)

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)

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.

• temperature (Sts4xTemperature) - Temperature response object.

Return type:Sts4xTemperature

class sensirion_i2c_sht.sts4x.commands.Sts4xI2cCmdMeasHighRes

STS4x command for a single shot measurement with high repeatability.

__init__()

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.

• temperature (Sts4xTemperature) - Temperature response object.

Return type:Sts4xTemperature

class sensirion_i2c_sht.sts4x.commands.Sts4xI2cCmdMeasMediumRes

STS4x command for a single shot measurement with medium repeatability.

__init__()

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.

• temperature (Sts4xTemperature) - Temperature response object.

Return type:Sts4xTemperature

class sensirion_i2c_sht.sts4x.commands.Sts4xI2cCmdMeasLowRes

STS4x command for a single shot measurement with low repeatability.

__init__()

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.

• temperature (Sts4xTemperature) - Temperature response object.

Return type:Sts4xTemperature

class sensirion_i2c_sht.sts4x.commands.Sts4xI2cCmdSoftReset

STS4x command for a soft reset.

__init__()

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.sts4x.commands.Sts4xI2cCmdReadSerial

STS4x command to read the serial number.

__init__()

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 serial number. Return type:int

Data Types

class sensirion_i2c_sht.sts4x.data_types.Sts4xRepeatability

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

HIGH = 1

High repeatability

MEDIUM = 2

Medium repeatability

LOW = 3

Low repeatability

Response Types

class sensirion_i2c_sht.sts4x.response_types.Sts4xTemperature(ticks)

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)

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.