hamjudo
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Re: VGA

Thu Dec 08, 2011 10:31 pm

Quote from Chris on December 8, 2011, 21:07
Quote from adric22 on December 8, 2011, 16:46
That $40 could be better spent on a monitor that can accept HDMI or DVI. I mean, you can pick up used LCD monitors for that amount of money these days.

Where, I will by 2, no 3..... seriously WHERE????

I am starting a new job in a week, but until 5PM on Friday December 9th, I work at a resale store in Ypsilanti Michigan, USA.

We don't ship them, but we do sell LCD monitors with DVI for $40 or less, but only when we have them in stock. I sold one this morning. We still have at least one more. We might still have 2. I doubt we have 3 in stock. The cheapest ones with HDMI are $45. There are a few. They are either small, or damaged. I've got a 22 inch one, with a centimeter long injury near the center of the screen. The wound is in the plastic in front of the LCD. Many programmers would not mind the damage, because they can move windows around to avoid the bad spot. It would drive other programmers crazy. Most people would not want to use it to watch movies.

We have at least half a dozen $25 monitors with only VGA connectors.

gsh
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Re: VGA

Fri Dec 09, 2011 8:30 pm

Quote from bradburts on December 8, 2011, 22:30
I thought the same but did not get much information on DSI from wiki. Isn't the RPI DSI?

The 2835 has a number of different video output formats, HDMI, DSI, DPI, SMI to name a few, it just requires the right GPIOs... Unfortunately after a chat with Eben earlier it looks like the DPI pins are not available as GPIOs (although it is possible they could be made available in a future revision)

If you know more about the RPI hardware or thought on this design then I would be interested.

Lets just say I know enough...
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liz
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Re: VGA

Sat Dec 10, 2011 11:02 pm

Quote from gsh on December 9, 2011, 20:30
Quote from bradburts on December 8, 2011, 22:30
I thought the same but did not get much information on DSI from wiki. Isn't the RPI DSI?

The 2835 has a number of different video output formats, HDMI, DSI, DPI, SMI to name a few, it just requires the right GPIOs... Unfortunately after a chat with Eben earlier it looks like the DPI pins are not available as GPIOs (although it is possible they could be made available in a future revision)

If you know more about the RPI hardware or thought on this design then I would be interested.

Lets just say I know enough...

He really does; hello! And I hope you stick around, because there are a bajillion questions about the SoC I am totally unqualified to answer, so it's always nice to see someone who knows it as well as you do pitch up here.
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gsh
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Re: VGA

Sun Dec 11, 2011 8:54 am

Happy to answer questions about the SoC as long as they don't reveal secrets!
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bradburts
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Re: VGA

Sun Dec 11, 2011 3:50 pm

Nice 2 know. No secrets plz, cause you would have to kill me afterwards.....

So to summarise (& plz correct me at any point); we only have DSI or HDMI at this revision of silicon/firmware but, for example, DPI may be possible if hard wired to the GPIO?

So to down convert to VGA we would need to chop the DSI serial bit stream, latch then convert to analogue via DAC or resistors?

I have not used DSI before so my big question is are there video modes and/or control to steer DSI bitstreams to align with VGA data streams?
Is it just the one channels that pixel data appears on? What is the minimum colour depth we can configure?
If pulses can be made to align then I just don't see why the convertor should be expensive.
Perhaps you could add your view, am I just being wildly optimistic ;) ?

gsh
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Re: VGA

Sun Dec 11, 2011 4:38 pm

The chip can output DPI, i.e. 24 bit parallel pixel with clock, horiz and vert sync and data enable signal. But the pins weren't wired up that way on the hardware, Eben suggested a future board mod could help here.

With that output you could just put the R G B signals into three DACs outputting at a peak of 0.7v, level convert the syncs to work at 5V rather than the standard 1.8V output and wire it straight up...

I guess you'll just have to hope a future board will have this output
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bradburts
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Re: VGA

Sun Dec 11, 2011 5:59 pm

Thanks.
I don't want to get caught wishing for things that aren't so!
Having 24 bits parallel pixel clock would open up a lot more display options, PSP screens have been mentioned b4.
From what you say it is possible to align the the clocks, that being so then VGA should be possible with the addition of a decode circuit which could be a few serial to parallel converters, counter and a some nands before the three DACs / resistors. The DACs were the most expensive at $1.5 each.
Wonder whos gonna make something first.

cfd
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Re: VGA

Sat Dec 24, 2011 8:34 pm

I'd love to have one of these things, but the lack of VGA makes it useless to me. I don't have a TV, but I have 3 VGA monitors of various ages.

Might USB to VGA be one temporary possible way round? I came across a StarTech.com USB to VGA External Video Adapter for £32. It turns an available USB 2.0 port into a VGA port.

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abishur
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Re: VGA

Sat Dec 24, 2011 8:44 pm

It's been my experience that USB to VGA adapters have tended to be resource hogs, if you plan on spending more money, my best solution is to purchase an HDMI -> VGA active adapter (a $5 passive one will not work) or a new monitor : P
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digital_addict
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Re: VGA

Sat Dec 24, 2011 9:23 pm

I have considered an hdmi to vga converter and they are available on ebay uk for around £44, but, Asda are allegedly selling a 15.6”, 720p, 1 hdmi input, hd ready tv, for £50 on Boxing Day. Don't know if it's one day only or not. It's got to be worth considering.

cfd
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Re: VGA

Sat Dec 24, 2011 9:44 pm

And then there's the UK TV licence on top of that...

Tomo2k
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Re: VGA

Sat Dec 24, 2011 10:25 pm

cfd said:


And then there's the UK TV licence on top of that…



Irrelevant. You only need a TV licence if you are receiving broadcast TV (or 'live' iPlayer) at the home/office address.

If you are only using the unit as a display and are not connecting it to an antenna/dish or 'live' iPlayer* to receive broadcast TV (or Teletext) then you do not need a TV licence.

If you don't currently have a TV licence, then unfortunately you will continue to get the regular threat letters from TV Licencing (they aren't actually the BBC, so don't blame them) that you already do, because they assume everyone in the UK watches broadcast TV, thus requiring a TV licence, regardless of whether they actually do or not.

After purchasing the display you will almost certainly get a visit from an inspector – politely tell them to go away. They have no legal powers and cannot enter your home uninvited, but they're just people and there's no point in being mean to them.

*Yes, if you watch TV programs live via iPlayer then you still need a TV licence. If you only watch programs through the catch-up service then at present you do not, though it's likely this will eventually change.

arm2
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Re: VGA

Mon Dec 26, 2011 10:10 am

Tomo2k said:


cfd said:


And then there's the UK TV licence on top of that…



Irrelevant. You only need a TV licence if you are receiving broadcast TV (or 'live' iPlayer) at the home/office address.




Not quite true in the UK, if you have ALL the equipment to recieve a broadcast TV signal you have to have a licenece!

A few years ago I was called as a witness for a neighbour who was being prosecuted for having no licence, I was able to confirm that the sound did not work and that the owner only discovered this when they tried lending it to someone.

The prosecution refered the magistrate to a precedent of an appeal. The magistrates did find them quilty but accepted they didn't use it, and only fined them £20 whilst other offenders on the same day were fined £200.

ALL the equipment seemed to mean TV + Aerial

hippy
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Re: VGA

Mon Dec 26, 2011 1:06 pm

arm2 said:


Not quite true in the UK, if you have ALL the equipment to recieve a broadcast TV signal you have to have a licenece!


See Part 4 of the Communications Act 2003 -

http://www.legislation.gov.uk/...../21/part/4

That in my experience has usually been interpreted as "anything capable of receiving broadcast TV requires a licence" but the wording of the legislation is not exactly clear. I know of cases not pursued, convictions obtained, and convictions overthrown on appeal.

Anyone in the UK who is planning to use a TV but not hold a TV licence would be best advised to seek professional legal advice on the issue and be prepared for having to defend their position in court.

CookieMonster
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Re: VGA

Wed Dec 28, 2011 11:24 pm

hippy said:


arm2 said:



Not quite true in the UK, if you have ALL the equipment to recieve a broadcast TV signal you have to have a licenece!


Anyone in the UK who is planning to use a TV but not hold a TV licence would be best advised to seek professional legal advice on the issue and be prepared for having to defend their position in court.


Wait...so in the UK you need a license to have TV receiver equipment?

Wow, I thought the US had found a way to tax everything. Yet over here they tend to "license" things that would affect other people. "Taxes" and "Fees" are what they call it when your action isn't likely to affect others.

Is there some historical reason it is called a license, such as the idea that the local oscillator might get mucked up and become an interfering transmitter? Or is it how the BBC gets some income, rather than the crass commercial messages we have here?

Tomo2k
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Re: VGA

Wed Dec 28, 2011 11:49 pm

It funds the BBC.

The original idea was to separate them from both Government and commercial interference, and it mostly works. I'm not entirely sure why it's called a licence though.

There is no commercial advertising or product placement on the BBC at all, and they are legally required to be impartial.

You wouldn't see anyone on (eg) Fox News laying into politicians on both sides, and this is a regular occurence on the BBC.

- It's expected for BBC journalists to lay into the BBC management on the BBC news if they appear to have done something daft. You'll never see that on a commercial channel!

BBC Worldwide is a commercial entity, and the BBC World Service is (was?) partially funded by the UK Foreign Office.

I'm very much in favour of the BBC, can you tell?

According to http://www.TVLicensing.co.uk:

If you don’t watch or record television programmes as they are being shown on TV, on any device, you don’t need a TV Licence.

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Montekuri
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Re: VGA

Thu Dec 29, 2011 12:30 am

TV license!?

When I was in Japan I heard something similar about NHK television.

It is some kind of donation to maintain the independent television.

hippy
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Re: VGA

Thu Dec 29, 2011 11:39 am

Tomo2k said:

According to http://www.TVLicensing.co.uk:
If you don’t watch or record television programmes as they are being shown on TV, on any device, you don’t need a TV Licence.


Full details at ... http://www.tvlicensing.co.uk/d.....Needed.pdf

BlueClogger
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Re: VGA

Thu Dec 29, 2011 11:55 am

If you haven't already got one, buying a UK TV licence is still going to be cheaper than getting legal advice (don't feed the parasites) and you can watch iPlayer live if you want to.

paulglave
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Re: VGA

Fri Dec 30, 2011 12:32 am

So, all I need to use an RPi with a VGA monitor is a TV license then?

Tomo2k
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Re: VGA

Fri Dec 30, 2011 12:52 am

paulglave said:


So, all I need to use an RPi with a VGA monitor is a TV license then?



No. This thread got more than a bit derailed!

Short answer: You don't. RPi does not support VGA monitors.

Longer answer - it's possible but expensive. Get a DVI-D or HDMI monitor (eg TV) instead, it's cheaper.

Benedict White
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Re: VGA

Fri Dec 30, 2011 1:13 am

Tomo2k said:


paulglave said:


So, all I need to use an RPi with a VGA monitor is a TV license then?


No. This thread got more than a bit derailed!

Short answer: You don't. RPi does not support VGA monitors.

Longer answer - it's possible but expensive. Get a DVI-D or HDMI monitor (eg TV) instead, it's cheaper.


Or an old TV that takes plain video in. Should be available for free, unless you are good at hagling in which case they will pay you to take it away.

Benedict White
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Re: VGA

Fri Dec 30, 2011 1:14 am

Oh... and if you have a TV and no TV licence do make sure you have no TV aerial.

BenJ
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Joined: Wed Aug 31, 2011 3:18 pm

Re: VGA

Fri Jan 06, 2012 6:57 pm

A careful search on eBay for "HDMI to VGA converter" gave me a few results for about $30 CAD shipped from China. One idea would be to sell these converters on the Raspberry Pi store so we wouldn't have to wait for shipping from China.

Here's one eBay listing

No1
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Re: VGA

Tue Mar 06, 2012 12:13 pm

Post launch, is there any plans for the next version of either of the current models or a new model, that might include VGA output?

Or at least an indication that you won't have time to look into the possibility before a certain milestone or date? (like the educational launch or maybe earlier if different teams/parts of the team are involved)

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