HDC2080: Reading from HDC2080/HDC2010

Irmantas Jamas

Part Number: HDC2080
Other Parts Discussed in Thread: HDC2010, HDC1080, SYSCONFIG, MSP430WARE, ENERGIA

Hello,

I was not able to find a C language programming example or library for reading temperature and humidity values from TI HDC2080 sensor via I2C when using STM32 MCU (I use CubeIDE environment). As I understand HDC2080 and HDC2010 could be programmed identically according to their datasheets and application report: https://www.ti.com/lit/an/snaa312/snaa312.pdf?ts=1590217153055. I am new to this, so application report did not help :/ I found an example only for HDC1080 which I assume has different application requirements. I would appreciate it if you could share any example or library in C language for reading temperature and humidity values using such sensor with me.

Thank you

over 3 years ago

0 Pavani Deepthi Tenneti over 3 years ago

TI__Expert 3270 points

Hello,

We have some basic C code on sysconfig for the HDC2010 as well as the HDC2080. You can configure the registers and look at the equivalent C code on the side.

Please refer to this link for HDC2010: https://dev.ti.com/sysconfig/index.html?product=ascstudio&module=/ti/sensors/humiditysensor/HDC2010

This is the link for HDC2080: https://dev.ti.com/sysconfig/index.html?product=ascstudio&module=/ti/sensors/humiditysensor/HDC2080

I hope this helps!

Regards,
Pavani Tenneti

0 Irmantas Jamas over 3 years ago in reply to Pavani Deepthi Tenneti

Prodigy 10 points

Hello,

After creating a library for HDC2080 using provided Sysconfig link and including it to my empty project generated using STM32CubeMX (CubeIDE) I receive errors:

c:\program files\stmicroelectronics\stm32cubeide\stm32cubeide_1.6.0\stm32cubeide\plugins\com.st.stm32cube.ide.mcu.externaltools.gnu-tools-for-stm32.9-2020-q2-update.win32_1.5.0.202011040924\tools\arm-none-eabi\bin\ld.exe: Temp and humidity sensor.elf section `.text' will not fit in region `FLASH'
c:\program files\stmicroelectronics\stm32cubeide\stm32cubeide_1.6.0\stm32cubeide\plugins\com.st.stm32cube.ide.mcu.externaltools.gnu-tools-for-stm32.9-2020-q2-update.win32_1.5.0.202011040924\tools\arm-none-eabi\bin\ld.exe: region `FLASH' overflowed by 8228 bytes
collect2.exe: error: ld returned 1 exit status
make: *** [makefile:65: New Project.elf] Error 1
"make -j8 all" terminated with exit code 2. Build might be incomplete.

I copied generated HDC2080 library files and included them in main.c as in example:

#include "HDC2080.h"

#include "mcu.h" /* for mcu_msWait() */

extern const HDC2080_Handle HDC2080_0;

int main(void)
{
/* init sensors with values specified in ti_sensors_config.c */
HDC2080_config(HDC2080_0);

}

Do you know what might be causing this problem?

Thank you.

0 Ren Schackmann over 3 years ago in reply to Irmantas Jamas

TI__Mastermind 40455 points

Hi Imantas,

It looks like the error is indicating the compiled code doesn't fit in your MCU's flash memory. The smallest STM32 I found has 128kb of flash, and I'm able to test this HDC code in a MSP430 with the same amount of flash. This is generic C code that hasn't been optimized for any platform. It would seem you need to clean or optimize other aspects of your project, or use an STM32 with more flash. Note that this HDC software does require division and multiplication of float data type, which can be messy for an MCU. It's best if your MCU has a hardware multiplier available. It may be possible to optimize other aspects of this software, but the HDC is going to require float multiplication to convert it's output format to temperature in celsius and relative humidity in percent.

thanks,

ren

0 Ren Schackmann over 3 years ago in reply to Ren Schackmann

TI__Mastermind 40455 points

Hi Imantas,

Slight correction: there are functions in the HDC code that perform the conversion without the use of float data type. You can remove the float functions from HDC2080.c if you don't wish to use them. Removing them saved me 1kb, and my binary was 3kb without them.

thanks,

ren

0 Irmantas Jamas over 3 years ago in reply to Ren Schackmann

Prodigy 10 points

Hello,

Did you just remove float HDC2080_humToFloatRelative(uint16_t x) and float HDC2080_tempToFloatCelsius(uint16_t x) functions from HDC2080.c? For some reason it did not reduce Flash overflow.

Also, I noticed that mcu.c which I downloaded from Sysconfig has empty i2C and Delay functions. Could you share any examples of these functions in C language when using HDC20X0 sensor? In my case MCU is STM32 which has only 16KB Flash memory :|

Thanks.

0 Ren Schackmann over 3 years ago in reply to Irmantas Jamas

TI__Mastermind 40455 points

Irmantas,

You can remove the two functions that use/return float datatype in HDC2080.c and HDC2080.h. If you do that, you need to make sure your main.c or equivalent doesn't call these functions. You can also remove the two float variables at the top of main.c if you're using our main.c.

The functions are intentionally blank, because we're not able to support specific platforms. The user must fill out the functions for their platform. This code was tested on MSP430, where I have code for those functions. On MSP430, the complete working example compiles to only 3kb. You should be able to run the example on your MCU with 16kb flash even without removing the float functions.

thanks,

ren

0 Irmantas Jamas over 3 years ago in reply to Ren Schackmann

Prodigy 10 points

Hello,

Where could instructions be found for exact MCU (in my case STM32L0) to create i2cInit, I2c_Transfer functions? For example, what did you use to write these functions for MSP430?

Thank you.

0 Josh Wyatt over 3 years ago in reply to Irmantas Jamas

TI__Guru* 91206 points

Dear Irmantas -

Much like our MSP430Ware and SimpleLink SDK offerings, STM offers SDK with an API based HAL for the peripherals (I2C included) on that MCU. I would suggest you refer back to that SDK and its documentation.

0 Ren Schackmann over 3 years ago in reply to Irmantas Jamas

TI__Mastermind 40455 points

Hi Irmantas,

If you need help filling out mcu.c for your platform, you can reference this example for a popular platform. It should be easy to understand.

e2e.ti.com/.../

thanks,

ren

0 Irmantas Jamas over 3 years ago in reply to Ren Schackmann

Prodigy 10 points

Hello,

Thank you for this example. Have you tried to test this mcu.c file with functions in C language? Could you share if you have?

Thanks.

0 Ren Schackmann over 3 years ago in reply to Irmantas Jamas

TI__Mastermind 40455 points

Irmantas,

Those are C functions in Arduino libraries. You will have to use libraries appropriate for your platform.

thanks,

ren

0 Irmantas Jamas over 3 years ago in reply to Pavani Deepthi Tenneti

Prodigy 10 points

Hello,

I tried to use this default HDC2080 code to read temperature with i2C functions implemented according to Arduino example (https://e2e.ti.com/support/sensors/f/sensors-forum/990448/faq-sysconfig-ascstudio-mcu-c-example-code-for-arduino-i2c/). For some reason HDC2080_tempToIntCelsius function always return a value of 125 which is maximum for this sensor (Temperature Threshold High). The same value is returned when using HDC2080_tempToFloatCelsius function. Also tried to measure humidity and received the maximum relative humidity value (100). Do you have any ideas what might be wrong?

Thank you.

0 Josh Wyatt over 3 years ago in reply to Irmantas Jamas

TI__Guru* 91206 points

Irmantas -

Would it help you to use an Energia/Ardunio sketch?

0 Irmantas Jamas over 3 years ago in reply to Josh Wyatt

Prodigy 10 points

Hello,

Yes, it might help if you could share them.

Thank you.

0 Josh Wyatt over 3 years ago in reply to Irmantas Jamas

TI__Guru* 91206 points

Irmantas -

Great - here is working sketch for the HDC2 parts.

HDC2_one_shot_01_2021_41.ino

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HDC2080: Reading from HDC2080/HDC2010