P20 pro OTG USB. What can you plug in?

  • 14 December 2018
  • 9 replies

Userlevel 6
Badge +5
Well loads apparently. if you're a propeller head like me, you'll l like this YouTube video:

Huawei P20 Lite USB OTG (USB On The Go) USB Host

This guy plugs in a USB CD, Hard disk, game controller and on and on... You can't fail to be impressed.

I just bought a cheapy

USB Type C to Type C, Type A, HDMI, Ethernet adaptor from fleaBay which looks like the attached pic. I think it does everything I want, but I'm not sure if you can reverse charge the phone from one of the USB ports, so I'll post up when I find out.

The HDMI looks great. I'm doing some microscope photography with my P20 Pro. Trying to get accurate focus on such a small phone screen is difficult, so hopefully I can plug it into my 24" LCD monitor and it will be easier.

The other thing I wanted to do was see who my phone is phoning. Or in other words, what Internet connections are being made. I noticed it's contacting Deutsche Telekom even though I haven't signed up for the Huawei cloud, or any cloud driven app. I think it's Hicare but we'll see.

I'm going to set up a Man in the Middle monitor with Wireshark, get the phone to talk to my laptop through the Ethernet port, bridge this over the the wifi connection for the Internet and monitor the Ethernet activity with Wireshark


I know, I know I probably should get out more lol.

Any road up, I'm waiting for the adaptor so will post more up when it arrives.

In the mean time, it would be good to hear from others that have got USB devices working on the OTG and this could be a bit of a list of working items.



9 replies

Userlevel 4
@picitup this is cool, my Mate 20 Pro handles games with ease, problem is gaming against ppl using pc and emulator, this adapter would come in handy for me where I could plug in my ps4 controller and many other things.
Userlevel 6
Badge +5
Brill thanks for posting up. The hardware on the P20/Mate20 is just brill.
Userlevel 6
Badge +5
Oops looks like I posted the pic of the adapter up twice. Shall I post it again in case anyone missed it? :-)

Well the adaptor arrived an hour ago so I had a play the second the package was opened and I'm pretty pleased.

First up was the HDMI. I tried it on our old LG smart TV. I plugged the HDMI cable in and you get notifications on your phone allowing you to go into desktop mode and turn the P20 into a mouse pad. All pretty easy to set up. The only issue with the TV is the desktop image is slightly larger than the screen, so if you maximise an app, you can't close it as the X is off screen.
Then I tried it with my trusty old Compaq monitor on HDMI. Works great and the screen size is correct so no issues there. It was my monitor I wanted it to work on mostly.

Then I plugged in my cheapy USB hub into the Type-A USB port and both my tracker ball and PC keyboard worked fine.

Next up was my old USB stick into the Type-A USB port and I could browse and view photos on it. I also have a Type-C to micro-sd adapter which I plugged into the Type-C port. And nothing. Not recognised, no messages etc. After a bit of playing, I think I've found that the Type-C port is power only. If you look at the pic above on the adaptor, the Type-A has the USB data fork icon thingy and the Type-C only has dashes.

I plugged my Huawei charger and Huawei cable into the Type-C port and voila! The P20 was charging.

So the upshot is, you can use your P20 on an external monitor with external keyboard and mouse and charge it at the same time. In effect it's like an octa core desktop pc lol. Lovely jubbly.

So far so good.

To see what Internet traffic flows out of the P20 I did the following:

I turned off wifi on the P20 and plugged the adapter into the USB port and the Ethernet port into my laptop with a cable. I then bridged the laptop and wifi connections in Control panel so the Internet was available on the Ethernet port. I could then browse the Internet on the P20. Then I started WireShark to monitor the traffic on the laptop Ethernet port which showed up some expected and unexpected communications.

So the setup was like this:

P20 -> Ethernet Adaptor -> Laptop Ethernet -> Bridge -> Laptop WIFI -> Access Point -> Internet

I'll post up another thread on this when I've had a proper play and put a link to it here if anybody else has an interest.

Well, 14 quid well spent :-)


Userlevel 6
Badge +5
Well now I have my adaptor, of course I've seen a better one so I ordered it. The new one has 3 USB 3.0 ports, VGA monitor,

HDMI, Ethernet and a PD Type-C charging port. On top of all that it's also a stand for your phone. I paid 26 quid off Amazon and it should arrive in January sometime.

I've attached a pic.


Userlevel 4
Great post @picitup

Love USB OTG. When you show someone that for the first time, blows their mind. I guess that's why I keep coming back to Android, so much fun.
Userlevel 6
Badge +5
Thanks @BrotherBear yes it's amazing what you can plug into otg and all the drivers are ready and waiting for you lol.

I'll post up a pic of the hub/stand when it arrives all wired up.

Merry xmas to you and yours.

Userlevel 6
Badge +5
Well the new adaptor arrived. Took bloody ages as I didn't spot it was posted from China lol. The first impressions are pretty good. The channel for the phone has a rubber guard inside so you don't scratch your phone. It's not glued in and falls out easily so I glued it last night.

First up was power. I plugged the device into my phone, started a long video (Norwegian Train Ride aka YouTube) and used my Huawei adaptor and Huawei cable to plug into the Type-C port on the adaptor.

The initial charge on the battery was 40%. After 90 minutes, the video was still playing and the charge was 100% so all good. I did try to charge my Moto G by connecting a cable from the power port on the adaptor to the phone, but it doesn't output power on that port. It doesn't matter as you can plug the cable directly into the phone and charge another phone that way.

Next up was HDMI. I noted above that the previous adaptor display was a little large for my TV, cropping the edges of the picture and losing the X to close a window. The new adaptor worked great and when I plugged it in, I was asked to select 1 of 3 screen resolutions, the first being just right for my TV. This feature may be new in Android Pie which I have on my P20. Nice feature!

I don't think I mentioned above, but I tried the old adaptor on my daughter's boyfriends' Samsung using HDMI. The phone said it was connected, but nothing on the tv screen. Nada. When we tried the Samsung and the new adaptor, it worked like a dream in both portrait, landscape and full screen on YouTube.

I suppose you get what you pay for!

Any road up, that's all for now. Over the weekend I'll plug in any USB device I can find and report back.

Have a good weekend all....

Userlevel 6
Badge +5
More Power?

Just a further check on powering multiple devices while charging the P20.

I have 2 Moto G (Moto1 and Moto2) phones and a P20 pro (Pro). I discharged them all using the famed Norwegian Train Ride video on Youtube and at the start of the test, the state of charge was:

Moto 1 23%
Moto 2 24%
Pro 61%

A USB hub was plugged into the dock and a keyboard and wireless mouse dongle into the hub. Moto1 and Moto 2 were plugged into the dock and the Huawei charger and cable plugged into the dock. A PC monitor was plugged into the VGA port.

The Pro was in Desktop mode and the Norwegian video was started.

Then the setup was left to (hopefully) charge. After an hour with the video running the charge states were:

Moto 1 65%
Moto 2 45%
Pro 92%

After 2 hours they were:

Moto 1 81%
Moto 2 57%
Pro 100%

So the upshot? You can use the P20 Pro with the dock, watch a video and power a mouse dongle, keyboard while charging the P20 and 2 phones!



Userlevel 1
i mean its pretty stupid that i have to buy one of these clunky hubs to get my controller to work because huawei doesnt support controller support trough bluetooth yet.... i mean we are living in 2019 these should be standard things like being able to unlock your bootloader.....