I own an anbernic RG353VS.
I just go the mini hdmi adapter to try out hdmi to a tv!

Here's what Iearned.

1. Once you've got everything hooked up.
If you already powered on your handheld.. sadly.. the anbernic will NOT auto detect hdmi output.

Instead... here's what happens if you already powered and then connected HDMI out.
a. it's stuck on handheld video for now.
b. it will not ouput to the tv screen.
c. press the reset button.. or turn off and turn on the system.
The device chooses output video on startup (right before anbernic logo)
d. You should now see video on the TV. Sadly though.. there is no video on your handheld.

Good luck!