Flekain
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Re: Why not VGA port on the Rpi ?

Sat Oct 15, 2011 11:35 am

Hey,
I already read the FAQs where it is said that if the Rpi does not have <something> included, it\'s because of the cost but I really don\'t understand why the Rpi does not have a VGA port:

- Screens with HDMI input are WAY most expensive that thoses who doesn\'t.
- The Rpi is a cheap computer, but if the required screen is expensive, I don\'t see the point.

Example:
In my case I need a cheap screen, I don\'t really care about his size but I do care a lot about his price.
- BenQ 18.5 VGA screen => 65 EURO
- LG 22 HDMI screen => 120 EURO

The gap between these two is HUGE (almost 100% !)

asb
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Re: Why not VGA port on the Rpi ?

Sat Oct 15, 2011 11:42 am

The VGA port issue has come up a number of times. If it was as simple as just adding the connector for an extra dollar or two I\'d imagine it would be done. See Eben Upton\'s answer to the VGA question in this interview:

http://interviews.slashdot.org/story/11 ... -questions

WizardOfOZ
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Re: Why not VGA port on the Rpi ?

Sat Oct 15, 2011 1:20 pm

Look for a monitor with a DVI-D connector instead of HDMI. HDMI is often marketed as a fairly high-end thing, and DVI-D monitors will usually be a fair bit less expensive. This even though HDMI and DVI-D carry the same signals, though with different connectors. A simple and inexpensive interface cable will allow you to connect HDMI with DVI-D.

Note: It *has* to say DVI-D, and not just \'DVI\' or DVI-A.

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abishur
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Re: Why not VGA port on the Rpi ?

Sat Oct 15, 2011 1:57 pm

As Asb said it\'s not just a matter of adding a VGA port. The GPU itself does not support VGA output. As the Slashdot article he linked states, they recognize that no VGA is a bit of an issue (especially with computer labs at schools) and they\'re looking into what they can do to resolve it without driving the price on up
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Bacan
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Re: Why not VGA port on the Rpi ?

Sat Oct 15, 2011 2:29 pm

A answer as I see it: This is a low cost learning tool. A kid at home is more likely to have a spare TV, than a VGA monitor. Cost is of key importance to get this into as many hands as possible to have them learn about computers. The ARM core and GPU processors, is produced in volume as a Commonly or Commercially Off The Shelf (COTS) System on a Chip (SoC) was designed for mass market use with TVs, not computer monitors. To keep the costs of this project down, only existing COTS parts were selected that fit the desired profile.

Flekain
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Re: Why not VGA port on the Rpi ?

Sat Oct 15, 2011 2:34 pm

Thanks to those who answered, it\'s more clear in my head now.
However, could somebody working on the \"no VGA\" issue could give us some update ?
As I said, VGA monitor = 60 EUR while HDMI one cost at least 120 EUR.
I happen to have a gift card on a website which expires in less than a month, and I would like to use it to buy a monitor which will be exclusively used with the Rpi.
So I\'m a little bit stuck right now :S

PiOfCube
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Re: Why not VGA port on the Rpi ?

Sat Oct 15, 2011 3:15 pm

Has there been any further testing with the Beagle VGA board or similar?
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Bacan
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Re: Why not VGA port on the Rpi ?

Sat Oct 15, 2011 3:19 pm

@Flekin - I feel for you. I\'ve yet to upgrade my TV to HDTV. So I\'m looking at a HDTV for use on the R-Pi and TV usage. And I\'m sliding down the screen size slope. The office supply store, Stapes, here in the US is offering a 20\" Hannspree discounted to ~$120.00 USD. I have a $50 credit that expires at the end of the month. I have also seen for sale at $250.00, a 25\" screen. For $350.00, a 32\" screen. I have a feeling I\'ll be spending 10x the R-Pi\'s computer price for the larger screen. :-)

jamesh
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Re: Why not VGA port on the Rpi ?

Sat Oct 15, 2011 3:22 pm

There is no update on the VGA issue. No work has been done on it. Few ideas tossed around but that\'s it.

DVI-D monitor £56 http://www.ebuyer.com/275023-hannspree- ... r-hw173dbb
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Lob0426
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Re: Why not VGA port on the Rpi ?

Sat Oct 15, 2011 4:17 pm

The perfect monitor for a RasPi would have a built in powered hub. Unfortunately there are not many of these around and they are generally more expensive when you do find them.

Composite video is not the best but it is more than adequate for programming. Many of us started out on machines like the Apples, the Timex-Sinclair and Tandy Color computers that were all originally composite video or less. Monitors were just not available for some of them or extremely expensive.

DVI-D is very good. When you design a device to be a low cost learning tool, you have to make compromises. I am relearning some programming using a nerd kit and the results from it are displayed on a 4x20 LCD. Of the the programming is on a nettop. You literally could learn to program on a LCD if that was all you had, so I consider having composite and HDMI a real step up. Once the RasPi\'s are in our hands I am sure someone will figure out an option for VGA. That\'s the power of the people, hundreds if not thousands put to work solving any problem. I already have a HDMI to VGA cable for my TV, an LCD, that will very likely work. If not I also have an HDMI to DVI that will work. We will figure out the right combinations as we go.
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obarthelemy
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Re: Why not VGA port on the Rpi ?

Sat Oct 15, 2011 5:01 pm

You\'ve got an in-between: a DVI screen, as long as it is DVI-D not DVI-A, will connect to the Pi\'s HDMI with a simple, passive, adapter cable.

Rasz
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Re: Why not VGA port on the Rpi ?

Sat Oct 15, 2011 6:54 pm

http://www.ebay.com/itm/DVI-24-1-male-V ... 3cb97e0bfb

US $2.19
If you look closely you will notice that its a proper DVI-D plug. No analog pins on DVI side
http://en.wikipedia.org/wiki/Digital_Visual_Interface
Did Chinese started cranking their own DVI receiver +DAC chips like they do with those crazy cheap USB 2.0 hubs?

At first i suspected its the angle and pins are there, just not visible, but

http://www.ebay.com/itm/HDTV-DVI-D-Dual ... 3f0efc3d5f

http://www.ebay.com/itm/HDTV-DVI-D-Dual ... 1e62e9c24c

http://www.ebay.com/itm/DVI-male-VGA-fe ... 27b057e156

same thing, proper DVI-D.

Of course it wouldnt be the first time Chinese invent something just so they can sell junk
[img]http://hackedgadgets.com/wp-content/upl ... -drive.jpg[/img]

eicristian
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Re: Why not VGA port on the Rpi ?

Sat Oct 15, 2011 9:05 pm

You could use an HDMI to VGA cable like this one for example: http://www.amazon.com/HDMI-VGA-HD15-Mal ... B001OLCHJ6

Johannes
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Re: Why not VGA port on the Rpi ?

Sat Oct 15, 2011 9:44 pm

The current design does not allow for a simple cable connection from the Raspberry Pi to a VGA monitor. This has been discussed at length in other threads and there is no need to post more \"solutions\" that don\'t involve an HDMI receiver chip and a DAC. A cable or simple discrete electronics are not going to cut it. All such methods rely on non-standard properties of the HDMI device, none of which are present in the Raspberry Pi. There may be a way the Raspberry Pi can be engineered to output a VGA signal, but if this is not going to be implemented in the release version (and it\'s not likely that it will), then it won\'t be possible to retrofit a VGA output.

DVI-D screens are about 20€ more than otherwise equivalent VGA monitors. Most DVI monitors also accept HDCP scrambled input signals, so they\'re for all intents and purposes HDMI monitors without audio. I suppose the markup for HDMI over DVI is simply a matter of market segmentation (or speakers).

If you\'re going to buy a new screen just for the Raspberry Pi, get one with digital input. Even if there were VGA-out on the Raspberry Pi, you\'d quickly regret buying a VGA-only monitor just to save 20€. Digital gives you a 100% sharp, rock solid picture, without syncing after every resolution change.

VGA would have been nice because it would have enabled lots of existing monitors to be reused. But implementing a complicated hack to make a digital-only SoC output VGA just so you can make a bad trade-off when shopping for a new screen? Not worth it. Don\'t skimp on the screen. It\'s the part of your computer system that you always look at. Don\'t waste your money on adapter cables that aren\'t going to work; buy a monitor with DVI-D or HDMI input.

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Lob0426
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Re: Why not VGA port on the Rpi ?

Sun Oct 16, 2011 12:51 am

@Johannes some LCD TV\'s do work with an HDMI to VGA cables. Not all of them will. My Vizio 42\" LCD will supposedly work as it has components in it to convert the signal. I definitely intend to test it out when the RasPi are available. This TV has a VGA port that is being used for my Windows Home Server right now.
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Johannes
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Re: Why not VGA port on the Rpi ?

Sun Oct 16, 2011 7:32 am

Then you have an HDMI TV that uses a VGA connector for HDMI input, for whatever reason the twisted minds of its inventors could fathom. It certainly wasn\'t the cheapest TV on offer, was it? That\'s what people are hoping for though: To buy a very low end monitor with just VGA-in and then use a cheap (i.e. passive) cable to connect it to the Raspberry Pi. That will not work. Don\'t steer them in that direction, unless you want a lot of disappointment on your conscience.

Rasz
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Re: Why not VGA port on the Rpi ?

Sun Oct 16, 2011 1:04 pm

[quote]Quote from Johannes on October 15, 2011, 22:44
The current design does not allow for a simple cable connection from the Raspberry Pi to a VGA monitor. This has been discussed at length in other threads and there is no need to post more \"solutions\" that don\'t involve an HDMI receiver chip and a DAC. A cable or simple discrete electronics are not going to cut it. [/quote]

Thats why i posted those links, look closely at
[img]http://usih.merchantrunglobal.com/Image ... gID=701180[/img]

no Analog pins on this DVI-VGA Adapter. Either Chinese started making their own converter chip for peanuts (like they do for dollar store USB 2.0 hubs), or its just an empty box inside with no connections at all.

Johannes
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Re: Why not VGA port on the Rpi ?

Sun Oct 16, 2011 2:47 pm

Rasz, no, that is not an empty box. It is a passive adapter for devices which accept HDMI signals on a VGA port.

The Raspberry Pi can not deliver a VGA signal and cheap VGA-only monitors can not accept a digital signal on their VGA ports. While there are (few) device combinations which can use these adapters, the combination of a Raspberry Pi with a cheap VGA monitor can not.

NoSuchNick
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Re: Why not VGA port on the Rpi ?

Sun Oct 16, 2011 2:49 pm

On the second eBay link you posted:
http://www.ebay.com/itm/HDTV-DVI-D-Dual ... 1e62e9c24c
There is this disclaimer:
[quote]NOTE:This is DVI-D 24+1 pin female port
This is just an adapter, the function is supported by the Graphic card, not the adapter, so read your user manual carefully to make sure it.[/quote]
I\'ve looked at similiar connectors on the german eBay, and often there is a similiar disclaimer. So i doubt that these actually convert anything.

One of the german disclaimers:
[quote]Achtung: Adapter ist nicht kompatibel zu Grafikkarten welche gemäß der DVI-Spezifikation gefertigt sind. Funktionsfähig nur dann, wenn am DVI-D Ausgang (24+1 Pin) der Grafikkarte ein analoges Signal anliegt. [/quote]
Roughly translates to:
[quote]Warning: This adapter is not compatible with graphic cards, which are manufactured according to the DVI specifications. Functional only when there is an analog signal present on the DVI (24+1 Pin) output of the graphic card.[/quote]

Rasz
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Re: Why not VGA port on the Rpi ?

Sun Oct 16, 2011 2:52 pm

\"Functional only when there is an analog signal present on the DVI (24+1 Pin) output of the graphic card\"

wow, why would anyone make such a kludge :(
thanks for the info

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Montekuri
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Re: Why not VGA port on the Rpi ?

Mon Oct 17, 2011 4:54 pm

There is a RCA (composite) output on the R-Pi board.
So we could use a RCA to VGA converter:
http://www.ebay.com/itm/TV-RCA-Composit ... 2a14e145ff

But I never used something like that. So, I doubt it would work.

Rasz
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Re: Why not VGA port on the Rpi ?

Mon Oct 17, 2011 5:04 pm

[quote]Quote from Montekuri on October 17, 2011, 17:54
There is a RCA (composite) output on the R-Pi board.
So we could use a RCA to VGA converter:
http://www.ebay.com/itm/TV-RCA-Composit ... 2a14e145ff

But I never used something like that. So, I doubt it would work.[/quote]

I did, we use them to connect monitoring cameras to LCD panels. Quality is ok for security cameras. Last time I bought those (exact same enclosure, model et350 or something) they were ~$35.

anwe79
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Re: Why not VGA port on the Rpi ?

Mon Oct 17, 2011 9:59 pm

If a cheap display is all you\'re after, pick up an old crt-tv with composite in. Around here (sweden) you could get one of those for next to nothing, people are throwing them away.

If you have a flatscreen with no composite input, get an old vcr with one. That would most likely be free (the actual tape drive doesn\'t have to work).

/Andreas

torrent99
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Re: Why not VGA port on the Rpi ?

Tue Oct 18, 2011 12:23 pm

[quote]Quote from Flekain on October 15, 2011, 15:34
Thanks to those who answered, it\'s more clear in my head now.
However, could somebody working on the \"no VGA\" issue could give us some update ?
As I said, VGA monitor = 60 EUR while HDMI one cost at least 120 EUR.
I happen to have a gift card on a website which expires in less than a month, and I would like to use it to buy a monitor which will be exclusively used with the Rpi.
So I\'m a little bit stuck right now :S[/quote]

Actually VGA monitor is generally £FREE these days if you go CRT, people are throwing them out left right & centre (check out Freecycle). All the more reason to find a cheap solution to the VGA question to take advantage of this free hardware.

There\'s always the Composite connection of course, but even though I learned to program on a black & white TV hacked to have such a connection, I don\'t think many people would put up with those resolutions now.

Lakes
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Re: Why not VGA port on the Rpi ?

Tue Oct 18, 2011 12:58 pm

Also, remember some scart sockets have a composite connection as well, another use for old tv`s.

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