External Monitor not Working
#1
Question 
I recently connected a NETUM NT-156B external monitor to the Pinebook Pro's USB-C output. Settings recognizes the monitor, but no image is displayed. The NETUM specs says it uses USB-C Alternate Display Port which is also what the Pinebook Pro Wiki calls for.

Any ideas? Duckduckgo has not revealed any solutions... Huh
  Reply
#2
From my quick check, it appears to use USB-C Alternate mode HDMI, which is a totally different animal.

Where did you see that it supported USB-C Alternate mode DisplayPort?

I wish vendors where much clearer in their descriptions.
--
Arwen Evenstar
Princess of Rivendale
  Reply
#3
(03-14-2021, 02:05 PM)Arwen Wrote: From my quick check, it appears to use USB-C Alternate mode HDMI, which is a totally different animal.

Where did you see that it supported USB-C Alternate mode DisplayPort?

I wish vendors where much clearer in their descriptions.
The manual says it uses "full-function USB-3.1 Type-C."  The Amazon listing for the touch-screen version says "In order to realize the touchscreen functions or single-cable power-data use, the connected devices (including smartphones and tablets) must support DisplayPort over Alternative Mode (DP ALT-MODE)." Which I took to mean that was the mode this device used.

I purchased it slightly used off eBay, which did not specify the type of USB-C connection, and of course, I didn't realize there was a difference until after I plugged it in and had to research why it wasn't working.

I suppose there's no way to change what the Pinebook uses....
  Reply
#4
(03-18-2021, 03:00 PM)sciolus Wrote:
(03-14-2021, 02:05 PM)Arwen Wrote: From my quick check, it appears to use USB-C Alternate mode HDMI, which is a totally different animal.

Where did you see that it supported USB-C Alternate mode DisplayPort?

I wish vendors where much clearer in their descriptions.
The manual says it uses "full-function USB-3.1 Type-C."  The Amazon listing for the touch-screen version says "In order to realize the touchscreen functions or single-cable power-data use, the connected devices (including smartphones and tablets) must support DisplayPort over Alternative Mode (DP ALT-MODE)." Which I took to mean that was the mode this device used.

I purchased it slightly used off eBay, which did not specify the type of USB-C connection, and of course, I didn't realize there was a difference until after I plugged it in and had to research why it wasn't working.

I suppose there's no way to change what the Pinebook uses....
Yes, your Amazon information does appear to be the correct USB-C alternate mode video type for the Pinebook Pro.

And no, their is zero chance of changing what the Pinebook Pro's USB-C video out can do. It's in the hardware.

One of my complaints about USB-C is that it tries to be everything to everyone. USB-C 4 takes that to a whole new level.


Now back to trouble shooting.
  • Do you have the ability to test this external monitor's HDMI input?
  • Their are 2 USB-C ports, if I recall correctly, did you use the correct one?
  • Can you power the external monitor from another source, and send it USB-C data?
In regards to the last, it's possible that the external monitor simply uses too much power. Our Pinebook Pros are not intended to supply a high amount of power to USB connected devices. So powering the external monitor from a power brick and using the USB-C for data might make it work.
--
Arwen Evenstar
Princess of Rivendale
  Reply
#5
I've been running an external HDMI monitor on my Pinebook Pro for several months. Armbian and an Anker USB C to HDMI adapter. Plug and play.
  Reply
#6
Hello forum,

This thread looks like the right place to report this, but feel free to redirect me if needed.

I received my brand new PBP a couple days ago and I am happy with it overall. I am test driving it with the default desktop environment (Manjaro KDE plasma). One unfortunate thing that I've found is that (contrary to my expectations) my external screen does not work via USB-C.

The screen is a Dell UltraSharp U3818DW with a native resolution of 3840x1600 at 60Hz and its USB-C input is spec'd as: Alternate mode with DP1.2, Power Delivery, and USB2.0. So judging from the specs, it should be compatible with the PBP video output. Also, this is a professional grade monitor and I expect that things are correctly implemented on its side (but you can never be sure, can you?). I am driving this monitor every day via its HDMI input, but sadly I haven't been able to test its USB-C input with a different computer.

Anyway, when I connect the monitor to the PBP with a direct USB-C to USB-C cable:
- The monitor's OSD displays "USB Type-C Plugged", which is good.
- The PBP starts charging the battery, which is good.
- Nothing else directly visible happens, but this appears in dmesg:

[ 1643.685532] cdn-dp fec00000.dp: [drm:cdn_dp_pd_event_work [rockchipdrm]] Not connected. Disabling cdn
[ 1643.929266] cdn-dp fec00000.dp: [drm:cdn_dp_pd_event_work [rockchipdrm]] Not connected. Disabling cdn
[ 1643.984981] typec_displayport port0-partner.0: No compatible pin configuration found:0000 -> 001c, 001c <- 0000
[ 1645.315793] usb 7-1: new high-speed USB device number 2 using xhci-hcd
[ 1645.506446] usb 7-1: New USB device found, idVendor=0451, idProduct=8442, bcdDevice= 1.00
[ 1645.506494] usb 7-1: New USB device strings: Mfr=0, Product=0, SerialNumber=1
[ 1645.506516] usb 7-1: SerialNumber: B1050089D092
[ 1645.560481] hub 7-1:1.0: USB hub found
[ 1645.560617] hub 7-1:1.0: 6 ports detected
[ 1645.965773] usb 7-1.5: new high-speed USB device number 3 using xhci-hcd
[ 1646.106643] usb 7-1.5: New USB device found, idVendor=0451, idProduct=82ff, bcdDevice= 1.00
[ 1646.106674] usb 7-1.5: New USB device strings: Mfr=0, Product=0, SerialNumber=1
[ 1646.106685] usb 7-1.5: SerialNumber: B1050089D092
[ 1646.169149] hid-generic 0003:0451:82FF.0003: hiddev97,hidraw2: USB HID v1.11 Device [HID 0451:82ff] on usb-xhci-hcd.1.auto-1.5/input0
[ 1646.265782] usb 7-1.6: new high-speed USB device number 4 using xhci-hcd
[ 1646.396762] usb 7-1.6: New USB device found, idVendor=0451, idProduct=82ee, bcdDevice= 1.00
[ 1646.396810] usb 7-1.6: New USB device strings: Mfr=0, Product=0, SerialNumber=3
[ 1646.396832] usb 7-1.6: SerialNumber: B1050089D092


- If I then press Fn+F3 to change the video output (to, let's say, "Switch to external screen"), nothing visible happens. And nothing else appears in dmesg either.

- I have tried flipping the USB-C connector (plugging it in the other way) and there is no difference, the same things happen as above.

- The cable is (I believe) from Apple; it has been used to drive a display in another setting (MacBook Pro with a different monitor by LG), so I believe it is good. I also tested with a different USB-C cable, the one that was supplied with the Dell monitor. It is much more stiff, so my preference is the Apple cable, but I don't think any of the cables are faulty.

Not surprisingly, if I look at System settings -> Display configuration, the screen does not show up (only the internal laptop screen is present).

Maybe the screen resolution is too high? I don't believe so, because I have an Asus TinkerBoard (RockChip RK3288, with a lower-end ARM Mali T760) that drives this screen via HDMI at its native resolution (@30Hz).

# uname -a
Linux xyz 5.11.16-1-MANJARO-ARM #1 SMP Wed Apr 21 12:27:08 UTC 2021 aarch64 GNU/Linux


Please let me know if there is any other diagnostics I can supply, or things I could try to troubleshoot this.

And thanks for making the PBP, it is a great piece of kit!
  Reply


Possibly Related Threads…
Thread Author Replies Views Last Post
  pinebook pro trackpad randomly stops working chewie 3 389 05-08-2021, 06:53 AM
Last Post: KC9UDX
  Some keyboard keys not working oddsocks 10 1,188 04-20-2021, 08:33 AM
Last Post: dsimic
  Microphone not working on Pinebook Pro vfr400racer 2 875 03-21-2021, 02:56 AM
Last Post: vfr400racer
  Anyone have a microphone working on a Pinebook Pro? Rachel Stone 5 1,306 02-20-2021, 05:21 AM
Last Post: dsimic
  Auto-wake behavior when external power is connected diodelass 7 3,133 12-05-2020, 01:19 AM
Last Post: dsimic
  Brand-new Pinebook Pro - keyboard not working guy100 8 3,168 10-09-2020, 10:49 AM
Last Post: guy100
  PBP Battery issues. Drainage on load with external accessories WhiteDragon 11 6,292 09-02-2020, 05:42 AM
Last Post: Nora No
  Keyboard - Some keys not working Christoph.Krn 1 1,220 08-27-2020, 07:15 PM
Last Post: rdmarsh
  How's 2.4 GHz Wi-Fi Working for You? diodelass 8 4,127 06-20-2020, 03:21 PM
Last Post: xmixahlx
  Microphone not working linuxfreund 0 971 06-09-2020, 02:11 PM
Last Post: linuxfreund

Forum Jump:


Users browsing this thread: 1 Guest(s)