This project implements a very simple graphical ammeter/powermeter on STM32 devices.
Hardware shopping list:
- Nucleo-F070RB or Nucleo-L432KC. Any other Nucleo board can be easily adapted as STM32 Cube APIs are used
- INA219 High Side DC Current Sensor Breakout
- SSD1306 128x64 display
Pinout for Nucleo-F070RB board
| Signal | STM32 IO | Nucleo connector |
|---|---|---|
| INA219 SCL1 | PB8 | CN10-3 |
| INA219 SDA1 | PB9 | CN10-5 |
| SSD1306 SCL2 | PB10 | CN10-25 |
| SSD1306 SDA2 | PB11 | CN10-18 |
Pinout for Nucleo-L432KC board
| Signal | STM32 IO | Nucleo connector |
|---|---|---|
| INA219 SCL1 | PA9 | CN3-1 |
| INA219 SDA1 | PA10 | CN3-2 |
| SSD1306 SCL3 | PA7 | CN4-6 |
| SSD1306 SDA3 | PB4 | CN3-15 |
| Button | PA3 | CN4-10 |
At reset the instantaneous values of current and power are displayed in text form on the display. When pressing the button a first time, a current measurement is performed at 10kHz and the mean value of the acquisition is displayed. When pressing the second button a second time, a power measurement acquisition at 10kHz sampling rate is started. When acqusition is finished, either because the button is released or the interal buffer is filled, the acquired data is displayed.