Document getting an external display working

[ksandom]

Task

• Document how to use an external display with the Astro.

Notes

My Astro is being repaired so I have not yet tried the latest firmware, so any small detail could be wrong. Here's my understanding from the previous firmware:

Scrcpy

I wrote a blog post about using scrcpy.

The only real downside to this method is that the quality and framerate drop when there are a lot of detailed changes like in a game or fast paced video. Text looks excellent.

Gemini (and cosmo?) HDMI adapter

The adapter needs to be plugged in with the display attached while the Astro boots. Resolution is limited to 720p, but is high quality, low latency, and the frame rate remains high.

You can attach peripherals like a hub, keyboard, and mouse to the other USB port.

Things to test

• Can you plug the adapter back in if you unplug it? Or do you have to reboot again to get it started again? Is the answer the same for a couple of seconds vs several seconds/minutes.
• Does the built in display stop working when the adapter is in use. - My display was already broken when I did it with mine, so I never got to test it.