what is the cost of HDMI?


Out of curiousity; how does this apply to the Raspberry Pi, and also ED's RetroPi? Both are technically end products
 
Out of curiousity; how does this apply to the Raspberry Pi, and also ED's RetroPi? Both are technically end products

As far as I can tell the RPi is already the end unit. ED would just be a reseller of the RPi if he offered it with the RetroPi. The RetroPi is just a glorified Case for the RPi.
 
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Now that I think about it there are passive HDMI to DisplayPort adapters though so it might not be totally impossible.

These passive adapters don't use DisplayPort at all, they are really just tunnelling the signals through the DisplayPort connector. This should not be confused with the DVI/HDMI situation: the transmission of RGB signals via HDMI is absolutely identical to single-link DVI-D, newer HDMI standards simply allow higher frequencies for larger resolutions.
But there also passive DisplayPort to HDMI adapters, suggesting that they're both compatible with a common standard. Since (to my knowledge) DVI-D can't carry audio, there must be some common compatibility mode which expands on DVI-D. What exactly is this format?
 
But there also passive DisplayPort to HDMI adapters, suggesting that they're both compatible with a common standard. Since (to my knowledge) DVI-D can't carry audio, there must be some common compatibility mode which expands on DVI-D. What exactly is this format?

It's exactly as Letalis says: DisplayPort++ detects when a passive HDMI adapter is plugged in and then simply shunts some of the pins to an internal HDMI port (whether that's just some pins on the video card or more complex circuitry to generate an HDMI signal is irrelevant).
The point is that DisplayPort++ is not producing HDMI, DisplayPort and HDMI are two incompatible technologies, and when you plug in an adapter it shuts off the "DisplayPort" stuff and just uses the port as an HDMI port.
Kind of the way the Pyra will have a USB3 port but the extra pins will be for an eSATA drive: the USB port is not eSATA, it's just being used as a convenient port, and the passive adapter merely pulls out the signal and provides it to the drive.
 
Since (to my knowledge) DVI-D can't carry audio, there must be some common compatibility mode which expands on DVI-D.

Graphics card manufacturers simply ship non-standard DVI->HDMI adapters that pass the audio signal through by using pins that are not being used while transmitting digital signals only.
 
If it were me, I'd just pay the $2-$4 per unit and not worry about whether we can or can't say it is HDMI.

Exactly.  There are a few pieces where the project will likely be paying licensing fees for standards.  SDXC, HDMI, USB, WiFi, 4G, SATA are all 'standards' which, as far as I know, are supported by standards organizations - many/most/all? of which are nonprofit.  The licensing fees may seem steep for an individual, but are typically small from a device production perspective.  The organizations use these fees to ensure compliance and compatibility.  Distinctly not evil.

https://en.wikipedia.org/wiki/SD_Association is the nonprofit standards organization for SDXC
https://en.wikipedia.org/wiki/VESA is the nonprofit standards organization for HDMI
http://www.usb.org/about is the nonprofit standards organization for USB
https://en.wikipedia.org/wiki/Wi-Fi_Alliance is the nonprofit standards organization for WiFi
4G - no idea who defines this one
https://en.wikipedia.org/wiki/Serial_ATA_International_Organization is the nonprofit standards organization for SATA

 
I think the reason you deem HDMI not evil is you are confusing its standards body with the VESA people, which do better products, without royalties.
 
But there also passive DisplayPort to HDMI adapters, suggesting that they're both compatible with a common standard. Since (to my knowledge) DVI-D can't carry audio, there must be some common compatibility mode which expands on DVI-D. What exactly is this format?

It's exactly as Letalis says: DisplayPort++ detects when a passive HDMI adapter is plugged in and then simply shunts some of the pins to an internal HDMI port (whether that's just some pins on the video card or more complex circuitry to generate an HDMI signal is irrelevant).
The point is that DisplayPort++ is not producing HDMI, DisplayPort and HDMI are two incompatible technologies, and when you plug in an adapter it shuts off the "DisplayPort" stuff and just uses the port as an HDMI port.
Kind of the way the Pyra will have a USB3 port but the extra pins will be for an eSATA drive: the USB port is not eSATA, it's just being used as a convenient port, and the passive adapter merely pulls out the signal and provides it to the drive.
So then technically any hardware that supports DisplayPort must also support HDMI? Or are the passive adapters just a de facto standard?
 
Well anyway DisplayPort at this point in production isn't happening, the Mainboard is designed and it has a micro-hdmi connector. I doubt Nikolaus wants to redesign around implementing a different connector or even more so fully supporting DisplayPort by adding the additional circuitry needed to do so.
 
Well anyway DisplayPort at this point in production isn't happening, the Mainboard is designed and it has a micro-hdmi connector. I doubt Nikolaus wants to redesign around implementing a different connector or even more so fully supporting DisplayPort by adding the additional circuitry needed to do so.

Oh I know, right now I'm just on a tangent trying to understand DisplayPort.

Edit: I made a separate thread for this to avoid polluting this thread any further https://boards.openpandora.org/topic/5600048-technical-differences-between-hdmi-and-displayport/
 
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So then technically any hardware that supports DisplayPort must also support HDMI? Or are the passive adapters just a de facto standard?
(These gor danged quotes!!!!!  ARGH!)
DisplayPort does not support HDMI.  DisplayPort and HDMI are completely different things.
DisplayPort++ support HDMI.  It is DisplayPort plus an HDMI passthrough.  The passive adapters tell the DisplayPort++ to connect to the HDMI.
If the device says "DisplayPort" then it is DisplayPort and cannot work with a passive HDMI adapter.  If it says "DisplayPort++" then it is DisplayPort plus HDMI and can work with the passive adapters.
 
DVI/HDMI have something in common that DisplayPort does not support: Just like with old CRTs driven over VGA, all RGB signals are being transmitted just in time. The transmission frequency is chosen based on the pixel clock and refresh rate of the chosen display mode - DisplayPort on the other hand uses fixed frequencies, the screen has to figure out the timings itself. Instead of transmitting RGB signals directly, DisplayPort uses data packages.

(VGA/)DVI/HDMI require extra hardware for each screen to feed like a PLL, which is the reason why most video cards only support 2-3 monitors over VGA/DVI/HDMI. DisplayPort on the other hand could be compared to USB - you can even use hubs and daisy-chaining to connect as many displays as the available bandwidth allows.
 
So then technically any hardware that supports DisplayPort must also support HDMI? Or are the passive adapters just a de facto standard?
(These gor danged quotes!!!!!  ARGH!)
DisplayPort does not support HDMI.  DisplayPort and HDMI are completely different things.
DisplayPort++ support HDMI.  It is DisplayPort plus an HDMI passthrough.  The passive adapters tell the DisplayPort++ to connect to the HDMI.
If the device says "DisplayPort" then it is DisplayPort and cannot work with a passive HDMI adapter.  If it says "DisplayPort++" then it is DisplayPort plus HDMI and can work with the passive adapters.
I really miss the old quote tags where Android didn't go completely nuts when cutting down the quotes.

I realize what you guys mean now, boy have I been dense today. Sorry about that. The "++" suffix went right over my head and it all makes sense now. So while still not solving the licensing issue, using a DisplayPort connector would, in addition to requiring a passive adapter for HDMI, also not work with pure DisplayPort monitors (only those supporting DisplayPort++).

Have I got it right this time around?
 
So then technically any hardware that supports DisplayPort must also support HDMI? Or are the passive adapters just a de facto standard?
(These gor danged quotes!!!!!  ARGH!)
DisplayPort does not support HDMI.  DisplayPort and HDMI are completely different things.
DisplayPort++ support HDMI.  It is DisplayPort plus an HDMI passthrough.  The passive adapters tell the DisplayPort++ to connect to the HDMI.
If the device says "DisplayPort" then it is DisplayPort and cannot work with a passive HDMI adapter.  If it says "DisplayPort++" then it is DisplayPort plus HDMI and can work with the passive adapters.
I really miss the old quote tags where Android didn't go completely nuts when cutting down the quotes.

I realize what you guys mean now, boy have I been dense today. Sorry about that. The "++" suffix went right over my head and it all makes sense now. So while still not solving the licensing issue, using a DisplayPort connector would, in addition to requiring a passive adapter for HDMI, also not work with pure DisplayPort monitors (only those supporting DisplayPort++).

Have I got it right this time around?
Closer.  A DisplayPort++ is still a DisplayPort, you can plug any regular DisplayPort monitor, it just also has the HDMI passthrough which works with passive adapters.
As for licensing, I have no idea. I can't find anything talking about the licensing of the HDMI in a DisplayPort++
It is HDMI, I suspect that there's got to be a license fee somewhere, but whether it's in the computer itself or attached to the adapter cable (or supposed to be attached to the adapter cable but no one actually pays it because China) I don't know.
In the end, however, the entire discussion is kind of moot: even if there is no license fees, the cheapest passive adapter I could find was $5, so unless ED sells fewer than 1250 it's still ultimately cheaper to just pay for the HDMI than an adapter.
Of course, that's assuming everyone makes use of the HDMI out which is definitely not going to be the case, but figuring out accurate numbers is boring.
 
Closer.  A DisplayPort++ is still a DisplayPort, you can plug any regular DisplayPort monitor, it just also has the HDMI passthrough which works with passive adapters.
As for licensing, I have no idea. I can't find anything talking about the licensing of the HDMI in a DisplayPort++
It is HDMI, I suspect that there's got to be a license fee somewhere, but whether it's in the computer itself or attached to the adapter cable (or supposed to be attached to the adapter cable but no one actually pays it because China) I don't know.
In the end, however, the entire discussion is kind of moot: even if there is no license fees, the cheapest passive adapter I could find was $5, so unless ED sells fewer than 1250 it's still ultimately cheaper to just pay for the HDMI than an adapter.
Of course, that's assuming everyone makes use of the HDMI out which is definitely not going to be the case, but figuring out accurate numbers is boring.
Sorry, I think I could've been more clear in my previous post. What I meant was if the DisplayPort++ output is "stuck" in HDMI mode (as it would in the hypothetical scenario with a switched connector on a Pyra) then only monitors supporting DisplayPort++ would work when using a DisplayPort cable, right? I think it works this way because from what I can tell there's no way to parse HDMI signals with DisplayPort (not ++) logic. Is this true?
 
I'm not sure what you mean.  It doesn't get "stuck" in anything: either it is outputting a DisplayPort signal, in which case any DisplayPort monitor can read it, or it has a passive HDMI adapter plugged in and only HDMI devices can use it.  There aren't any monitors that support DisplayPort++: either they are DisplayPort or they are HDMI and it either needs an adapter or not.
 
I'm not sure what you mean.  It doesn't get "stuck" in anything: either it is outputting a DisplayPort signal, in which case any DisplayPort monitor can read it, or it has a passive HDMI adapter plugged in and only HDMI devices can use it.  There aren't any monitors that support DisplayPort++: either they are DisplayPort or they are HDMI and it either needs an adapter or not.

I mean as in the monitor receives HDMI on the DisplayPort connector. This is probably a strictly theoretical scenario anyway as the EDID of the monitor will say it supports DisplayPort which should make the output circuitry toggle the DisplayPort++ back into DisplayPort signaling. But this is what I mean with "stuck" (emphasis on the quotation marks here); if for some reason the output circuitry erroneously decides to permanently output HDMI, is the monitor expected to recognize that it's getting an HDMI signal (as if a passive HDMI -> DisplayPort adapter is used) or would it most likely just not understand what is going on? This is pretty much what I meant by monitors supporting DisplayPort++.

I know I sound really slow but I had never heard of DisplayPort++ before I participated in this thread (and since then I've learnt that pretty much every laptop actually has DisplayPort++ despite nobody mentioning it).
 
Sorry, but this strikes me as a rather pointless discussion.

The motherboard is full.  The SoC outputs HDMI more or less native.  DisplayPort of any form would require additional components and drivers.  Done is done - a substantive change like that should not even be considered this late in the develpment.

Regardless of how some would like to politicize DisplayPort Vs DVI Vs HDMI Vs other based on merits and faults real or imagined, HDMI is what we're going to have.  I'm good with that - it works with every monitor, TV and stereo system I plan to plug video output into.
 
I mean as in the monitor receives HDMI on the DisplayPort connector.

I've never heard of such a thing.  Monitor either has an HDMI connector on it and receives HDMI or it has a DisplayPort connector on it and receives DisplayPort (or it may have both connectors).  I've only ever heard of DisplayPort++ in reference to a source.
I can't think of any reason why a monitor would use a DisplayPort connector for receiving HDMI signals.  I guess it could and I've just never heard of it, but I don't think so.
Anywho, assuming that a DisplayPort++ does, unfortunately, get stuck in HDMI mode, the DisplayPort circuitry broken and only the HDMI signals are functional, then the only thing that would work would be a passive HDMI adapter.  I suspect that a theoretical DisplayPort++ monitor would attempt to use DisplayPort mode and only switch itself to HDMI mode if it also detects a passive HDMI adapter cable.

Don't worry about "sounding slow", if I start to sound exasperated it's because it makes such perfect sense in my head and I'm having trouble explaining it properly.  We'll get through it eventually. :)
 
Sorry, but this strikes me as a rather pointless discussion.

The motherboard is full.  The SoC outputs HDMI more or less native.  DisplayPort of any form would require additional components and drivers.  Done is done - a substantive change like that should not even be considered this late in the develpment.

Regardless of how some would like to politicize DisplayPort Vs DVI Vs HDMI Vs other based on merits and faults real or imagined, HDMI is what we're going to have.  I'm good with that - it works with every monitor, TV and stereo system I plan to plug video output into.

Despite all the talk surrounding DisplayPort I realize ED won't abandon HDMI this late, however the licensing issues remain and I think it would be healthy to discuss what our options are (and as I've learnt in the past couple of days, various bits and bobs from DisplayPort is definitely not a way around that).

I mean as in the monitor receives HDMI on the DisplayPort connector.

I've never heard of such a thing.  Monitor either has an HDMI connector on it and receives HDMI or it has a DisplayPort connector on it and receives DisplayPort (or it may have both connectors).  I've only ever heard of DisplayPort++ in reference to a source.
I can't think of any reason why a monitor would use a DisplayPort connector for receiving HDMI signals.  I guess it could and I've just never heard of it, but I don't think so.
Anywho, assuming that a DisplayPort++ does, unfortunately, get stuck in HDMI mode, the DisplayPort circuitry broken and only the HDMI signals are functional, then the only thing that would work would be a passive HDMI adapter.  I suspect that a theoretical DisplayPort++ monitor would attempt to use DisplayPort mode and only switch itself to HDMI mode if it also detects a passive HDMI adapter cable.

Don't worry about "sounding slow", if I start to sound exasperated it's because it makes such perfect sense in my head and I'm having trouble explaining it properly.  We'll get through it eventually. :)
That answers my question wonderfully actually, I think we're on the same page now. Thank you for your patience, I didn't pick up on any exasperation  :)

(As a non-native english speaker I am glad to have also learnt the meaning of "exasperated" today ;)  )
 
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