jt562
Posts: 3
Joined: Thu May 24, 2012 8:17 am

Dual Display?

Thu May 24, 2012 8:21 am

Has anyone tried using both HDMI and Video composite output at the same time (like you could on a pc video card).

So a TV linked to HDMI and another TV via video composite?

:?: :?:

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nick.mccloud
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Joined: Sat Feb 04, 2012 4:18 pm

Re: Dual Display?

Thu May 24, 2012 12:24 pm

AFAIK it will detect and use the HDMI and only revert to the composite if it has to.

I've read nothing over the previous months that says you can use two screens at the same time but as using the word impossible only invites a storm of responses I won't say that :D

jt562
Posts: 3
Joined: Thu May 24, 2012 8:17 am

Re: Dual Display?

Thu May 24, 2012 12:28 pm

Okay thanks, I was just interested as I have ordered my pi but won't be here for a while and so couldn't test myself.

If anyone has managed to do it please post your results!

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grumpyoldgit
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Re: Dual Display?

Thu May 24, 2012 1:03 pm

I'm sure I read it on here that if HDMI is detected composite is switched off.

Joe Schmoe
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Re: Dual Display?

Thu May 24, 2012 1:23 pm

nick.mccloud wrote:AFAIK it will detect and use the HDMI and only revert to the composite if it has to.

I've read nothing over the previous months that says you can use two screens at the same time but as using the word impossible only invites a storm of responses I won't say that :D
Generally, the best way to use an online forum to find out how to do something is to assert that it is impossible.

They'll be coming out of the woodwork to prove you wrong.
And some folks need to stop being fanboys and see the forest behind the trees.

(One of the best lines I've seen on this board lately)

jt562
Posts: 3
Joined: Thu May 24, 2012 8:17 am

Re: Dual Display?

Thu May 24, 2012 1:28 pm

Its impossible?

(thought id help get some solutions :P)

happyt
Posts: 1
Joined: Fri May 25, 2012 9:14 am

Re: Dual Display?

Fri May 25, 2012 9:17 am

So, I assume then that I couldn't have a dual display with different contents on each....?

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grumpyoldgit
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Re: Dual Display?

Fri May 25, 2012 9:27 am

happyt wrote:So, I assume then that I couldn't have a dual display with different contents on each....?
What we are saying is that you can't even have a dual display with the same contents.

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nick.mccloud
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Re: Dual Display?

Fri May 25, 2012 10:22 am

I know a way of having two displays - just plug two in, one in to HDMI and one in to composite. Look at the HDMI screen. The composite will display a reference image of black.

Joe Schmoe
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Joined: Sun Jan 15, 2012 1:11 pm

Re: Dual Display?

Fri May 25, 2012 12:09 pm

Or setup VNC, as has been described several times in various threads. Then you can use your VGA monitor to see a brand new, independent desktop. This solves both the problem of "How to use my VGA monitor" as well as the dual monitor issue.
And some folks need to stop being fanboys and see the forest behind the trees.

(One of the best lines I've seen on this board lately)

MarshallBanana
Posts: 24
Joined: Sat Jan 21, 2012 9:19 pm

Re: Dual Display?

Fri May 25, 2012 6:18 pm

on a more serious note someone from the foundation/broadcom mentioned on a similar thread quite some time ago that indeed hdmi/composite are impossible to drive at the same time, but if you manage to use the dsi connector (i.e. kidnap some bc engineer and let him produce a new gpu-binary for your dsi-connected screen) you could in fact have a working dual display setup...

tl:tr wait for dsi screen

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SN
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Contact: Website

Re: Dual Display?

Fri May 25, 2012 6:59 pm

The other way of course is if Matrox built an HDMI version of their Triplehead2go (or the 2 screen version whose name escapes me right now)
Steve N – binatone mk4->intellivision->zx81->spectrum->cbm64->cpc6128->520stfm->pc->raspi ?

eriolloan
Posts: 3
Joined: Thu Feb 07, 2013 2:59 pm

Re: Dual Display?

Thu Feb 07, 2013 3:39 pm

Sorry for bumping an (somewhat) old topic (tell me if I should start another thread for this question and I will).

Being a recent owner of a rPi I'm just learning what it's capable of. Obviously I've now learned it can't display to both a HDMI screen and composite screen...

The question is: can you get a dual-screen setup using either of these (HDMI preferably) and a USB display (something like this : http://www.amazon.com/MIMO-UM-720S-Scre ... 13-5045031) ?

I guess it should work, but can anyone more knowledgeable than I am confirm this ?

Thanks in advance.

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RaTTuS
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Re: Dual Display?

Thu Feb 07, 2013 4:13 pm

possibly will work - but probably not worth it.
it's a lot more expensive than other RPi - ;)

you will be able to get dual screen when the foundation release the DSI display [not any time soon - but who knows]

why do you need / want a dual display
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Cloudcentric
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Re: Dual Display?

Thu Feb 07, 2013 4:44 pm

I know everything about nothing"

eriolloan
Posts: 3
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Re: Dual Display?

Thu Feb 07, 2013 5:04 pm

Wow, thanks for your quick answer !

Rather want than need... I'm a graphic designer, illustrator and like to sketch, jot down short novel ideas, collect pictures... Really a multitasker. I kind of anticipated the dual screen trend that could have emerged from the microsoft courier (http://www.youtube.com/watch?v=GlpftPSuXe4)... obviously it just won't happen soon, if ever :(
I'd use it to work as well as a digital artwork in itself : a unique interactive book-like device is an artistic argument...

I see Chalkboard Electronics is to release 7" capacitive screens soon which might interest me if I could get the USB equivalent for the other "page".

btw this page on the wiki has some DSI related information, maybe not enough to get a grocery list out of it...
http://elinux.org/Rpi_Screens#DSI_port

Is there somewhere where I could find more details (DSI placement on the Pi board, known-to-work displays...) ?

eriolloan
Posts: 3
Joined: Thu Feb 07, 2013 2:59 pm

Re: Dual Display?

Thu Feb 07, 2013 5:10 pm

Thanks cloudcentric (I didn't know this existed). But I'd need each screen to display a different signal and form what I get about this device I'd get the same thing displayed twice...

Cloudcentric
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Re: Dual Display?

Thu Feb 07, 2013 6:12 pm

I do not know if these are supported, have never tried, and will likely need to be plugged into a USB Mains Power Hub, also would need drivers ???

http://www.ebay.co.uk/itm/USB-2-0-UGA-t ... 0227485871
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RaTTuS
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Location: North West UK

Re: Dual Display?

Fri Feb 08, 2013 9:01 am

think outside the box,
if you want 2 displays then use 2 RPi's + display

it's the communication between the 2 machines that may be more of an issue

I've used multiple monitor systems since forever ....

my 1st job in the computer industry we have mono + cga monitors on IBM PC's and even used mono monitors as well as vga / xga until XP killed them off - then had dual display cards or 2 cards ....
...

in collage we had SGI workstations with 2 monitors or used 2 at once ... when we could get at them
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Jim JKla
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Re: Dual Display?

Fri Feb 08, 2013 9:07 am

They asked Terry Pratchett why he had a six monitor system his answer was "Because I can't have eight" :lol:
Noob is not derogatory the noob is just the lower end of the noob--geek spectrum being a noob is just your first step towards being an uber-geek ;)

If you find a solution please post it in the wiki the forum dies too quick

pluseinn
Posts: 5
Joined: Sat Sep 29, 2012 2:03 am

Re: Dual Display?

Sun Feb 09, 2014 2:19 pm

I have a "solution" for those who just want to monitor the outgoing HDMI signal on a cheap composite screen.

You need two devices that will cost about $50

Search the following on ebay or aliexpress:
1. HDMI Splitter 1x2 Y
2. HDMI to composite converter

I am using a setup like this to monitor outgoing videowith a band on stage. I needed the secondary display to preview what is going on the backdrop behind me.

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