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Dual Screens on Raspberry Pi0W

Tue Jan 02, 2018 3:09 am

I am working on a project with my Raspberry Pi 0W and I want to know if/how I can hook up two displays.
I want the two displays to be touchscreen and connected by HDMI. I have selected these screens already. If I get an HDMI Splitter (Mini-HDMI to 2 Female HDMI), can I connect 2 displays, and display one large image.

Can I connect 2 touchscreen displays to a Raspberry Pi 0W using HDMI? And How?

HermannSW
Posts: 1014
Joined: Fri Jul 22, 2016 9:09 pm

Re: Dual Screens on Raspberry Pi0W

Tue Jan 02, 2018 9:13 pm

I cannot help with HDMI connected screens, but connecting two screens via SPI to Pi Zero[W] is definitely possile:
viewtopic.php?f=43&t=193722&p=1215277&s ... 4#p1217930

I did not use touch screens, but you can do since fbtft allows for that.

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https://github.com/Hermann-SW/fork-raspiraw      https://github.com/Hermann-SW/userland
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HermannSW
Posts: 1014
Joined: Fri Jul 22, 2016 9:09 pm

Re: Dual Screens on Raspberry Pi0W

Tue Jan 02, 2018 9:17 pm

I cannot help with HDMI connected screens, but connecting two screens via SPI to Pi Zero[W] is definitely possile:
viewtopic.php?f=43&t=193722&p=1215277&s ... 4#p1217930

I did not use touch screens, but you can do since fbtft allows for that.

Image
bookmark list: https://stamm-wilbrandt.de/en/Raspberry_camera.html

https://github.com/Hermann-SW/fork-raspiraw      https://github.com/Hermann-SW/userland
https://github.com/Hermann-SW/wireless-control-Eachine-E52-drone      https://twitter.com/HermannSW

_ThaNerd_
Posts: 30
Joined: Tue May 09, 2017 3:20 pm

Re: Dual Screens on Raspberry Pi0W

Sat Dec 08, 2018 6:18 pm

Can this be done with a Raspberry Pi 3? I am trying to output 2 diff views, one on a 9" touchscreen and one on a regular 9"...

aBUGSworstnightmare
Posts: 1207
Joined: Tue Jun 30, 2015 1:35 pm

Re: Dual Screens on Raspberry Pi0W

Mon Dec 10, 2018 6:46 am

Don't know if you guys know about dual frame buffer beta testing viewtopic.php?f=63&t=216399&start=275&s ... 7a2854b81c

This should work on a zero too once officially released.
_ThaNerd_ wrote: Can this be done with a Raspberry Pi 3? I am trying to output 2 diff views, one on a 9" touchscreen and one on a regular 9"...
How do you want to connect your screens to RPi3?
IMG_0685.jpg
Google Nexus 7in (1280x800 portrait mode) and 18.5in Full-HD (1920x1080; rotated to portrait) - both connected directly to LVDS4CM3L expandable baseboard
IMG_0685.jpg (137.76 KiB) Viewed 1087 times
Here's a video, showing dual frame buffer beta testing
https://www.youtube.com/watch?v=HFYg63suLoM

Code below gives you an idea how to show different video on each frame buffer

Code: Select all

screen -dmS vid1 sh -c 'omxplayer --display=4 --win "0 0 800 480" /home/pi/Videos/trailer0_1080p.mov; exec bash'
screen -dmS vid1 sh -c 'omxplayer --display=2 --win "0 0 1280 1024" /home/pi/Videos/trailer1_1080p.mov; exec bash'

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 21460
Joined: Sat Jul 30, 2011 7:41 pm

Re: Dual Screens on Raspberry Pi0W

Mon Dec 10, 2018 10:26 am

Note that the Pi0 does not have the DSI connectors, so you are limited to HDMI and whatever you can plug in to the GPIO (DPI, SPI etc).
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
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_ThaNerd_
Posts: 30
Joined: Tue May 09, 2017 3:20 pm

Re: Dual Screens on Raspberry Pi0W

Mon Dec 10, 2018 3:12 pm

Wow that is some great info! Thanks!

I want to create either a custom app or use a web-browser in my Pi to show live content from a database derived from a web hosted db. So one screen will show some content of this db while the other shows some other content of this db.

Currently I'm using a DSI 7" original raspberry pi touchscreen and a non-touchscreen 7" hdmi. The dsi one works while the hdmi one is black (nothing is shown). But if I to use a Pi Zero I will not be able to use a DSI screen so was wondering how will a Pi Zero work with 9" or larger screens...

Going to find more info in regards to the board they are using in the youtube vid you've mentioned.
aBUGSworstnightmare wrote:
Mon Dec 10, 2018 6:46 am
Don't know if you guys know about dual frame buffer beta testing viewtopic.php?f=63&t=216399&start=275&s ... 7a2854b81c

This should work on a zero too once officially released.
_ThaNerd_ wrote: Can this be done with a Raspberry Pi 3? I am trying to output 2 diff views, one on a 9" touchscreen and one on a regular 9"...
How do you want to connect your screens to RPi3?

IMG_0685.jpg

Here's a video, showing dual frame buffer beta testing
https://www.youtube.com/watch?v=HFYg63suLoM

Code below gives you an idea how to show different video on each frame buffer

Code: Select all

screen -dmS vid1 sh -c 'omxplayer --display=4 --win "0 0 800 480" /home/pi/Videos/trailer0_1080p.mov; exec bash'
screen -dmS vid1 sh -c 'omxplayer --display=2 --win "0 0 1280 1024" /home/pi/Videos/trailer1_1080p.mov; exec bash'

aBUGSworstnightmare
Posts: 1207
Joined: Tue Jun 30, 2015 1:35 pm

Re: Dual Screens on Raspberry Pi0W

Mon Dec 10, 2018 7:04 pm

_ThaNerd_ wrote: Wow that is some great info! Thanks!

I want to create either a custom app or use a web-browser in my Pi to show live content from a database derived from a web hosted db. So one screen will show some content of this db while the other shows some other content of this db.

Currently I'm using a DSI 7" original raspberry pi touchscreen and a non-touchscreen 7" hdmi. The dsi one works while the hdmi one is black (nothing is shown). But if I to use a Pi Zero I will not be able to use a DSI screen so was wondering how will a Pi Zero work with 9" or larger screens...

Going to find more info in regards to the board they are using in the youtube vid you've mentioned.
you can try the multi framebuffer beta with your setup.

Sorry man, but you will not find that much info on the LVDS4CM3L board on the internet!
That's a custom baseboard for Compute Module CM3L developed by me. So most info so far is posted on this forum.
This custom board is using HDMI + DPI. HDMI+DSI (official Raspberry 7in display) is possible too (see picture below).
IMG_0677.jpg
IMG_0677.jpg (55.19 KiB) Viewed 974 times
Sorry, but the board is not for sale.

_ThaNerd_
Posts: 30
Joined: Tue May 09, 2017 3:20 pm

Re: Dual Screens on Raspberry Pi0W

Tue Dec 11, 2018 3:07 pm

Oh I see, well that board would have made things much easier I assume :)

Anyhow will test things out and see where I get, thanks for the info!
aBUGSworstnightmare wrote:
Mon Dec 10, 2018 7:04 pm
_ThaNerd_ wrote: Wow that is some great info! Thanks!

I want to create either a custom app or use a web-browser in my Pi to show live content from a database derived from a web hosted db. So one screen will show some content of this db while the other shows some other content of this db.

Currently I'm using a DSI 7" original raspberry pi touchscreen and a non-touchscreen 7" hdmi. The dsi one works while the hdmi one is black (nothing is shown). But if I to use a Pi Zero I will not be able to use a DSI screen so was wondering how will a Pi Zero work with 9" or larger screens...

Going to find more info in regards to the board they are using in the youtube vid you've mentioned.
you can try the multi framebuffer beta with your setup.

Sorry man, but you will not find that much info on the LVDS4CM3L board on the internet!
That's a custom baseboard for Compute Module CM3L developed by me. So most info so far is posted on this forum.
This custom board is using HDMI + DPI. HDMI+DSI (official Raspberry 7in display) is possible too (see picture below).
IMG_0677.jpg

Sorry, but the board is not for sale.

aBUGSworstnightmare
Posts: 1207
Joined: Tue Jun 30, 2015 1:35 pm

Re: Dual Screens on Raspberry Pi0W

Tue Dec 11, 2018 6:26 pm

Using LVDS displays with an RPi is a piece of cake with this board. That's why I designed it as I always ended up with the 'wrong' LVDS4PI add-on on hands (LVDS4PI is for single channel LVDS interface only, and I've designed two versions as there are two data mappongs).

Well, still haven't decided yet if it's worth the effort of running a kickstarter campaign for the LVDS4CM3L ... Will have to find some EMS and get some quotes first.
Need to make some free time for doing this ...

_ThaNerd_
Posts: 30
Joined: Tue May 09, 2017 3:20 pm

Re: Dual Screens on Raspberry Pi0W

Tue Dec 11, 2018 8:49 pm

It's hard to tell if they'll be demand or not...
aBUGSworstnightmare wrote:
Tue Dec 11, 2018 6:26 pm
Using LVDS displays with an RPi is a piece of cake with this board. That's why I designed it as I always ended up with the 'wrong' LVDS4PI add-on on hands (LVDS4PI is for single channel LVDS interface only, and I've designed two versions as there are two data mappongs).

Well, still haven't decided yet if it's worth the effort of running a kickstarter campaign for the LVDS4CM3L ... Will have to find some EMS and get some quotes first.
Need to make some free time for doing this ...

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