H2O flow meter

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H2O flow meter is based on hall H2O sensor and the STM32L053R8 mcu.
Thanks to this SW/HW you can take under control your water consumptions.
The consumption are show via Virtual Com on the PC but are also stored in the internal EEPROM of STM32L053R8.

Hall H2O flow counter, see here
We used this sensor.

For this example we used the:

Thanks the STM32 ecosystem is easy to transfer this project on other STM32

Below some images of the messages received on PC via Virtual Com.

The I/O used on NUCLEO-L053R8 are in the red boxes below.
NOTE: The jumper JP1 must be present if you power the NUCLEO via an external USB power supply.

  • JP1 – must be present if you power the NUCLEO via an external USB power supply.
  • D15/D14 – (PB6/PB7) are reserved for I2C
  • D13 – (PA5) is the Green LED present on the NUCLEO
  • A0 – (PA0) is ADC reserved for monitor external power supply
  • D0/D1 – (PA4/PA2) are used for USART2 for communicate to the PC (Virtual Com via NUCLEO USB)
  • PC13 – is the HALL input signal (also connected to B1, Blue Button present on the NUCLEO)
  • D7 – (PA8) is reserved for Input
  • D9 – (PC7) is reserved for Output

Below there is the pins allocation in the IOC file

Schematic is below, here there is the PDF file.

We display the result on the PC using Virtual Com port, thanks to emulator integrated in the NUCLEO board.
For more info concerning printf via usart see this tutorial.

Also we save the H2O Flow Count in internal EEPROM with Date and Time (by RTC).
For more info regarding RTC see the AN4759 and this tutorial.

Extra Info

Power Supply NOTE:


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