Heartbeat LED during init script

[barebox+mailing at cookiesoft.de]

Hey everyone,

we use the barebox bootloader in on of our products.
Because of some norms we need to make a memtest of the RAM. To do that, we use the provided memtest tool.
So one of our our scripts is `/env/init/10-memtest`, which has just `memtest -tc` in it.


The other script is `/env/init/05-heartbeat` which contains 

#!/bin/sh

led -b board-red 100 1000

So, at first the 05 script is executed, afterwards the memtest script.

The problem is, that during the memtest the led does not blink, but flashes red the whole time. After the memtest is done, the blinking is done perfectly fine, but not during the memtest.

I create a small video to showcase this exact problem: https://imgur.com/a/9sxHTcm

Can anybody tell me why the barebox isn't able to keep up with the blinking as well as how to mitigate that?

Greetings,
Marcel