FiPy Temperature Sensor

[lloureiro]

It have, temperature sensor?

[rcolistete]

Yes, it has the MCU temperature, use machine.temperature(), but it is not yet documented... (even the Pycom development documentation) :

import machine
machine.     # type <Tab> keyboard to see the all objects of the machine context
    __class__       __name__        main            ADC
    BROWN_OUT_RESET                 CAN             DAC
    DEEPSLEEP_RESET                 HARD_RESET      I2C
    PIN_WAKE        PWM             PWRON_RESET     PWRON_WAKE
    Pin             RMT             RTC             RTC_WAKE
    SD              SOFT_RESET      SPI             Timer
    Touch           UART            ULP_WAKE        WAKEUP_ALL_LOW
    WAKEUP_ANY_HIGH                 WDT             WDT_RESET
    deepsleep       disable_irq     enable_irq      flash_encrypt
    freq            idle            info            mem16
    mem32           mem8            pin_sleep_wakeup
    remaining_sleep_time            reset           reset_cause
    rng             secure_boot     sleep           temperature
    unique_id       wake_reason
machine.temperature()   # in F
    116
(_ - 32)/1.8            # in C
    46.66667

[lloureiro]

@rcolistete Thank you for booth answers :)

[jcaron]

@rcolistete that’s probably the CPU’s temperature, which is most certainly quite different from ambient temperature, isn’t it?

[rcolistete]

@jcaron Yes, it is the ESP32 internal temperature sensor, always reading above the environment temperature (15-25 C more).

[jcaron]

@lloureiro so the answer depends on what temperature you want to measure: the CPU temperature or the ambient temperature.

For the former you can use machine.temperature as suggested by @rcolistete

For the latter you’ll need an external sensor. The Pysense board has one (though at least on the first version it wasn’t perfect due to not being isolated enough from sources of heat such as the CPU, IIRC). Or you could connect any external temperature sensor using SPI or I2C or any number of other interfaces. I would not recommend a sensor with an analog output as the ESP32 ADCs are not very precise.