T9602

Library for the IP67-rated T9602 I2C temperature and relative humidity sensor.

#include <T9602.h>

Inherits from NW_PlainSensor

Public Functions

	Name
	T9602() Instantiate the T9602 sensor class.
bool	begin(uint8t ADR =DEFAULT_ADDRESS) Begin communications with the T9602 sensor.
bool	updateMeasurements() Measure relative humidity [%] and temperature [degrees C].
uint16_t	setReadings(uint16_t n) Set how many readings updateMeasurements() takes (statistics are computed over them). Clamped to T9602_CAPACITY.
void	setStats(bool enable) Enable or disable humidity and temperature std and sterr columns in printDataHeader()/printDataRow().
uint16_t	getReadingCount() Number of valid readings stored by the last updateMeasurements().
uint8_t	getStatus() Status bits from the last data fetch.
float	getHumidity() Return the stored relative humidity [%]: the mean of the last updateMeasurements(), NW_ERROR (-9999) when none was valid.
float	getHumidityMean() Humidity mean [%] over the stored readings.
float	getHumidityStd() Humidity standard deviation [%].
float	getHumiditySterr() Humidity standard error [%].
float	getHumidityMedian() Humidity median [%] (mean of the middle pair for even N).
float	getTemperatureMean() Temperature mean [C] over the stored readings.
float	getTemperatureStd() Temperature standard deviation [C].
float	getTemperatureSterr() Temperature standard error [C].
float	getTemperatureMedian() Temperature median [C].
float	getTemperature() Return the stored temperature [degrees C].
size_t	printDataHeader(Print & out) override Print the summary columns a logger writes: the means, with the statistics columns when they are enabled.
size_t	printDataRow(Print & out) override Print one summary row, in printDataHeader()’s column order.
const char *	name() const override The part’s name, for the status file and for a sketch’s own use.
uint8_t	defaultAddress() const override The address it answers at unless the logger says otherwise.
bool	wake(uint8_t address) override Come back on the bus after the logger cut the sensor rail to sleep.
bool	acquire() override Take this row’s readings, for printDataRow() to print.
bool	sleep() Dummy function to enable sleep mode.
size_t	printHeader(Print & out) Print the header matching printReading(): “Humidity [%],Temp Atmos [C],”. No statistics columns: one reading has none.
size_t	printReading(Print & out) Print the stored reading, each value followed by a comma. Does not acquire: call updateMeasurements() first, or use logReading().
size_t	logReading(Print & out) Take ONE reading and print it: the one-reading primitive for collecting many readings to a file.
void	beginReadings(uint16_t n =0) Begin a run of readings. The T9602 is not a Schema 1 device, so n is only the number of logReading() calls to follow; nothing is declared to the sensor.
void	endReadings() End a run of readings.

Public Attributes

	Name
constexpr uint8_t	DEFAULT_ADDRESS Default I2C address. The part fixes it: there is no strapping pin and no register to change it.

Public Functions Documentation

function T9602

T9602()

Instantiate the T9602 sensor class.

function begin

bool begin(
    uint8_t ADR_ =DEFAULT_ADDRESS
)

Begin communications with the T9602 sensor.

Parameters:

ADR_ I2C address. Defaults to 0x28. This library cannot change this, but this option exists in case you make this change elsewhere.

Return: true if the sensor acknowledges its address on the bus.

function updateMeasurements

bool updateMeasurements()

Measure relative humidity [%] and temperature [degrees C].

Return: true if every reading was valid. false if any timed out (stale or no data, sensor in command mode, or no sensor); the stored values are NW_ERROR (-9999) when none was valid.

Takes setReadings(n) readings (default one). Each sends a measurement request, then fetches data until the sensor’s status bits report a valid (not yet fetched) measurement, or until T9602_TIMEOUT_MS passes; readings are therefore independent measurement cycles. The getters return the mean of the readings taken.

function setReadings

uint16_t setReadings(
    uint16_t n
)

Set how many readings updateMeasurements() takes (statistics are computed over them). Clamped to T9602_CAPACITY.

Return: The number actually set.

function setStats

void setStats(
    bool enable
)

Enable or disable humidity and temperature std and sterr columns in printDataHeader()/printDataRow().

function getReadingCount

uint16_t getReadingCount()

Number of valid readings stored by the last updateMeasurements().

function getStatus

uint8_t getStatus()

Status bits from the last data fetch.

Return: 0: valid data; 1: stale data (already fetched since the last measurement cycle); 2: sensor in command mode (start-up); 3: no data (no sensor on the bus).

function getHumidity

float getHumidity()

Return the stored relative humidity [%]: the mean of the last updateMeasurements(), NW_ERROR (-9999) when none was valid.

function getHumidityMean

float getHumidityMean()

Humidity mean [%] over the stored readings.

function getHumidityStd

float getHumidityStd()

Humidity standard deviation [%].

function getHumiditySterr

float getHumiditySterr()

Humidity standard error [%].

function getHumidityMedian

float getHumidityMedian()

Humidity median [%] (mean of the middle pair for even N).

function getTemperatureMean

float getTemperatureMean()

Temperature mean [C] over the stored readings.

function getTemperatureStd

float getTemperatureStd()

Temperature standard deviation [C].

function getTemperatureSterr

float getTemperatureSterr()

Temperature standard error [C].

function getTemperatureMedian

float getTemperatureMedian()

Temperature median [C].

function getTemperature

float getTemperature()

Return the stored temperature [degrees C].

function printDataHeader

size_t printDataHeader(
    Print & out
) override

Print the summary columns a logger writes: the means, with the statistics columns when they are enabled.

Parameters:

out Where to print.

Return: Bytes printed.

“Humidity [%],Temp Atmos [C],” with std and sterr columns after each value when setStats(true) is on. Pass a File to write the card, Serial to write the monitor. Distinct from printHeader(), which is the burst interface and carries no statistics.

function printDataRow

size_t printDataRow(
    Print & out
) override

Print one summary row, in printDataHeader()’s column order.

Parameters:

out Where to print.

Return: Bytes printed.

Takes no reading: it prints what the last updateMeasurements() left, which is what lets a caller write the same row to two sinks without acquiring twice.

function name

inline const char * name() const override

The part’s name, for the status file and for a sketch’s own use.

function defaultAddress

inline uint8_t defaultAddress() const override

The address it answers at unless the logger says otherwise.

function wake

inline bool wake(
    uint8_t address
) override

Come back on the bus after the logger cut the sensor rail to sleep.

function acquire

inline bool acquire() override

Take this row’s readings, for printDataRow() to print.

function sleep

bool sleep()

Dummy function to enable sleep mode.

Currently not used. Instead, we simply power the sensor down.

function printHeader

size_t printHeader(
    Print & out
)

Print the header matching printReading(): “Humidity [%],Temp Atmos [C],”. No statistics columns: one reading has none.

Parameters:

out Any Print destination (SdFat File, Serial, …).

Return: Bytes written.

function printReading

size_t printReading(
    Print & out
)

Print the stored reading, each value followed by a comma. Does not acquire: call updateMeasurements() first, or use logReading().

Return: Bytes written.

function logReading

size_t logReading(
    Print & out
)

Take ONE reading and print it: the one-reading primitive for collecting many readings to a file.

Return: Bytes written.

function beginReadings

void beginReadings(
    uint16_t n =0
)

Begin a run of readings. The T9602 is not a Schema 1 device, so n is only the number of logReading() calls to follow; nothing is declared to the sensor.

function endReadings

void endReadings()

End a run of readings.

Public Attributes Documentation

variable DEFAULT_ADDRESS

static constexpr uint8_t DEFAULT_ADDRESS = 0x28;

Default I2C address. The part fixes it: there is no strapping pin and no register to change it.

Updated on 2026-10-04 at 04:51:47 +0000