Simple Battery Reading Script

I’m trying to get a simple battery reading script working, but everytime I flash it to the board, it just goes into DFU mode (pulsing magenta) Can someone help me out?

#include "application.h"

FuelGauge fuel;

void setup() {
void loop() {
    Particle.publish("battery%", fuel.getSoC());

Hmm, pulsing magenta is not DFU mode (blinking yellow), but actually means your firmware it being updated. Since ‘pulsing’ doesn’t exists, it’s either blinking (updating) or breathing (Safe mode).
Depending on which of the two it is, different things might be going on, could you double check and report back?

How do you build?
I guess you are not using Web IDE, since Build wouldn’t (shouldn’t) allow you to build for Electron unless your target and installed system firmware are compatible.
And as @Moors7 said, your symptoms suggest that your application firmware and your installed system are not compatible.

Try flashing your application via Web IDE and set the target to On the device (x.y.z)

Can you post a video of the actual RGB LED feedback to avoid confusion of terms?

@ScruffR I tried posting a video but won’t let me upload. I will find a quick mirror site.

It is definitely pulsing, so I think you are correct about safe mode.

That seems to be breathing white, which indicates I think.