ESP32 WROOM32 internal temperature

[0wwafa]

I have this device:

I uploaded the latest firmware update 2v25.11

In a program I wrote some time ago I have E.getTemperature() to get the internal temperature.
But now I get it's NOT IMPLEMENTED?!

Why?
I don't know which firmware version I had before but the program was working!

>E.getTemperature()
ERROR: >> jshReadTemperature Not implemented
=NaN
> 

[0wwafa]

In the source I read:

// the temperature from the internal temperature sensor
JsVarFloat jshReadTemperature() {
#if defined(STM32F1) || defined(STM32F4)
  // enable sensor
  ADC_TempSensorVrefintCmd(ENABLE);
  jshDelayMicroseconds(10);
  // read
  JsVarFloat varVolts = jshAnalogRead(JSH_ANALOG1 | JSH_ANALOG_CH17, false) / (JsVarFloat)65535;
  JsVarFloat valTemp = jshAnalogRead(JSH_ANALOG1 | JSH_ANALOG_CH16, false) / (JsVarFloat)65535;
  JsVarFloat vSense = valTemp * V_REFINT / varVolts;
  // disable sensor
  ADC_TempSensorVrefintCmd(DISABLE);
  return ((V_TEMP_25 - vSense) / V_TEMP_SLOPE) + 25;
#else
  return NAN;
#endif
}

But ESP32 WROOM has the sensor and in micropython it's working!

ets Jun  8 2016 00:22:57

rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:2
load:0x3fff0030,len:4892
ho 0 tail 12 room 4
load:0x40078000,len:14896
load:0x40080400,len:4
load:0x40080404,len:3372
entry 0x400805b0
MicroPython v1.24.1 on 2024-11-29; Generic ESP32 module with ESP32
Type "help()" for more information.
>>> import esp32
>>> esp32.
HEAP_DATA       HEAP_EXEC       NVS             Partition
RMT             ULP             WAKEUP_ALL_LOW  WAKEUP_ANY_HIGH
__dict__        gpio_deep_sleep_hold            idf_heap_info
raw_temperature                 wake_on_ext0    wake_on_ext1
wake_on_touch   wake_on_ulp
>>> esp32.raw_temperature()
124
>>> 

[SimonGAndrews]

Looks like it was changed (file /targets/esp32/jshardware.c) on April 26 this year in commit 973d26a. (see image of code change below).
It seems there has always been a note saying the functionality used an undocumented library function. But not clear why it was changed in April.

In 2018 this was published on the subject.

The newer versions of the espressif IDF have examples of reading the sensor here. But only for more recent processors eg c3 ,s3 etc. In fact there is a comment in the example in IDF V4.3

saying the ESP32 does not support the method. But we could try to implement it in the Esp32C3 build (which uses the newer IDF) if that would help.

Sorry not an answer for you @0wwafa , but a bit of info.

[gfwilliams]

Thanks @SimonGAndrews!

I'm not 100% sure why that was removed, but I believe this was merging in someone else's changes for IDF5 builds.

I've put that change back now so cutting edge builds should be ok - but it might be nice to get the proper sensor in for C3/etc

But I'm not quite sure what you were using getTemperature for but it varies wildly on the ESP32 so would need calibrating - mine reports 107 which I'm pretty sure isn't right.

[0wwafa]

Thanks @gfwilliams ! It works.
By the way: tempc = Math.round((E.getTemperature()-32)*500/9) / 100;
To have the temp in Celsius.

[0wwafa]

P.S.
Your ESP32 is at 41 degrees celsius. It seems right to me. Way colder than mine.
My esp32 says it's around 56 degrees and putting a finger on it "confirms it".
Why is it running so hot? With micropython it's quite cold.

Hmm I disabled BLE and now it's way colder.
5 degrees celsius less than before.

[gfwilliams]

Interesting - it could be BLE means it's not sleeping so much? I'm not sure.

ESP chips do run hot though - Wifi consumes a lot of power so if that's enabled it's just going to end up getting warm