#platformio-stm32-ampere this is no my project, but something I found on http://atcnetz.blogspot.com/
STM sells these discovery boards with e-ink display for a few bucks. The STM32L053 contains a chip to measure current.
So what Aaron Christophel did, was write an arduino sketch to turn the demo-board into a very accurate ampere-meter (nano micro milli)
Just flash sketch to board. On top of E-ink display is connector, connect 2 pins right hand side. Between ground and free pin on connector (+) feed your device.
Here is a discription on howto setup on raspberry
get platformio.ini from this repo platformio init --board nucleo_l053r8 platformio init platformio lib install U8g2
cp sketch under src to your src/dir
place the variant.h from this repo under ~/.platformio/packages/framework-arduinoststm32/variants/NUCLEO_L053R8#
and type pio run
firmware.bin is somewhere under .pioenvs directory
platformio stm32 discovery amperemeter
============================ to get data on serial port, connect PA9 AND PA10
on orange pi adapt armbianEnv -- overlays = uart1 uart3
this gets you an extra port /dev/ttyS3
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