How to troubleshoot blank screen?

[iberjoinansel]

I get a blank screen on the display and splash screen on HDMI forever, no cpu light after it blinks a few times on boot.
How can I troubleshoot this? are there any logs persisted on the sd card that I can read?

[jdlcdl]

The standard rpi rainbow splash on hdmi is normal while the RPi is looking to boot. As well, the waveshare hat's backlight will illuminate as soon as it's powered on but it will remain black until your seedsigner has booted (30-50 seconds depending on which model you have).

If nothing happens after that, then you should suspect problems on your microsd card. Make sure that it's version 0.6.0, you can download the image for all supported boards here and follow the instructions for verifying and installing here.

If you are already confident that you've done all of this, verify that you indeed have the correct image; there are 2 images for raspberry pi zero. The image named like "pi0" is for the original boards regardless of wifi/bluetooth, while the image named like "pi02w" is for the later/faster rpi zero version 2 model.

There are no logs to refer to in troubleshooting, if all else fails, try to boot a standard raspi-os image and verify that your pi board hardware is working properly, and of course, make sure that solder connections on the header are solid as bad connections would cause problems with the waveshare hat.

[DesobedienteTecnologico]

-dev release allows you to use the HDMI, but is only recommended for developers.

Thanks for the explanations @jdlcdl