Faulty emonPi board?

I’ve been running my emonPi setup for a few years now but it stopped working yesterday (around 2PM if the data in my HA install is to be believed). So I shut it down and tried rebooting it only to get stuck with “Booting…” on the LCD. So got a new SD card and the latest image, tried that same thing.

So still failing, took it apart, plugged in the HDMI only for it to start going through the boot sequence get to the bit where it sets the hostname to emonPi, complain about “no DMA platform data” and then spew a continuous stream of “sysrq: HELP: …” messages. Tried redoing the SD, same result.

Took it completely to bits and just tried the Pi on it’s own, boots to the prompt. Plugged the emonPi board back in, same stream of errors. Does this mean my board is “dead” or is there something else I can do to try and work out what is going on with the board?

Thanks in advance.

If your getting the same result with a newly flashed SD card image then that does sound like a raspberry pi fault… it could be worth trying a new SD card if you have one spare to rule out a worn out card?

Welcome, Gavin, to the OEM forum.

Er, @TrystanLea Gavin wrote that he’s already put the image onto a new SD card, so to me it looks as if the “emon” front end is stopping the Pi from booting. Does the Feb24 image work on an older emonPi with the serial interface?

Ah read that the wrong way round.

Ok that’s a good clue, but not sure yet why that would be. Will have to check that on an emonpi here, though pretty sure it was fine when I tested it last. I will confirm.

Searching for this error elsewhere suggests something to do with the UART/serial as your suggesting @Robert.Wall. Both the emonPi2 and original emonPi use the serial port /dev/ttyAMA0 in the same way (only difference being baud rate) so perhaps this suggests invalid voltages coming from the emonPi board due to a blown component perhaps?

Il double check with the latest image here but it sounds like the same error persisted both on old and new images that you tried @Q_Division ?

Booted up an emonPi v1 on the latest image, that’s working fine which suggests a fault with the emonPi measurement board itself. Could you take a close up picture of the top and bottom of the board? Your also welcome to post the board back to us and we can take a look at it here for you.

I’ve hooked up the board over serial with nothing connected beyond power and that seemed OK.

Just tried the Nov23 image and that booted as a complete unit, did spot some error/warnings about undervoltage though:

hwmon hwmon1: Undervoltage detected!"

Re-trying the Feb24 image with the serial attached and will see if that sheds any light on it.

Here are photos of the board for ref., nothing jumps out at me.


OK, can’t tell you what the difference is but the Feb24 one worked after this flash.

It’s looking like the original issue is a fault of the SD card as I can’t currently import the old data (it’s complaining about partitions)