I’m modifying the firmware to return real and apparent power from both CTs in order to use these to calculate the power factor in a Virtual Feed in emoncms. I’ve bought 4 emonpi units and am doing this with all of them.
I have completed this on one emonpi unit - happy days!
On the second unit however, the firmware builds but PlatformIO fails to upload. Upon trying to connect to /dev/ttyAMA0 it fails with message: “*** [upload] Device or resource busy”
Any ideas? Do I need to open the unit and start checking connections?
Nice work.Have you stopped emonhub?
sudo service emonhub stop
Also I think platformio will require
The page I followed last time had both of those in it. Part 1/3: PlatformIO open-source embedded development ecosystem - Blog | OpenEnergyMonitor
Today I was using Firmware Modification - Guide | OpenEnergyMonitor which doesn’t mention either.
However, even stopping emoncms and using sudo to run pio … I’m getting the same error.
I’m going to work on the next one and see if it behaves differently.
Never mind! It helps if you stop the right service.
I stopped emoncms … now having had lunch I paid attention and stopped emonhub.
Excellent. Ah yes, it’s emonhub you need to stop. Emonhub is a python service which reads the serial data from the emonPi on
/dev/ttyAMA0 and posts to Emoncms / MQTT.
The section 3b “Using ttyAMA0 GPIO to upload direct to emonPi” at the end of the Platformio blog post mentiones that stopping emohub is required.