Constant green and red light.

Simrose

Pi4b
Argon one case v1 with expansion
Argon one official psu
Official Retropie 4.7.1
Wd blue 500gb SSD
SD card slot empty
Nothing in usb ports

When I boot retropie I have constant
Green and Red light lit.
(This does not effect any performance I'm just trying to find out what might be configured wrong)

I understand the Red should be lit but green should not be on constant.

I could not find any solutions in this forum but found an old post in raspberrypi forum that by using this line
dtparam=sd_poll_once in boot config.txt it will fix it by stopping the pi constantly checking for sdcard when one is not present.

I enabled this line and it does stop the constant green light being lit. But I would like to know if the constant green light is just because if booting from usb or if I have something with my settings wrong.

It's original retropie image with just a few line changes in config.txt I disabled 4k with the method advised in this forum. And disabled the boot screens with cmdline as advised here.

If anyone can shed some light on this matter 😉 i would appreciate it.

Thanks
Sim

mitu

The green light is caused by the Linux kernel sdcard driver polling - see https://github.com/raspberrypi/linux/issues/3286. As you found out, it can be disabled via configuration.

Simrose

@mitu
Thanks for getting back to me so quick.

From reading that post it looks like with the newer firmwares it is not needed.

What would your recommendation be keep the line and have no constant green light or remove the line and ignore the green light.

Is there somewhere I can check if when I have the line removed and a green light if their is errors being logged about it.

Thanks for your help, I'm still enjoying retropie and have used it daily with my family for the past few years.

Thanks
Sim

mitu

@simrose said in Constant green and red light.:

From reading that post it looks like with the newer firmwares it is not needed

No, the issue I linked says the 'poll once' parameter was not implemented (at the time) for the Pi4, but was made available and functional with a newer firmware for the Pi4.

What would your recommendation be keep the line and have no constant green light or remove the line and ignore the green light.

Keep the config.

Simrose

@mitu
Sorry I did not read it properly.

That's great.

Many thanks again for your help.

Sim