> +++ Steve Wiseman [2011-05-24 08:04 +0100]: >> On Tue 24/05/11 07:16 , "P.J.G. Long" wrote: >> >>> The low end console/display market seems to be moving HDMI, they are >>> becoming more common on netbooks. I can see for a number of low end >>> users using it as the cheap route to a display. See the Raspberry! Looking >>> at the feedback I think there may be a market for the Balloon as the up >>> market interfacable unit >> This still isn't a use case. >> Is it simply that, without a monitor connection of some sort, it's not a 'proper computer? > To some degree, yes. It's certainly not a convenient computer, although ssh and > remote X goes a long way to solving this in a different way. > Well, we have hardware graphics acceleration available. Without monitor output of some sort it is limited to being only an inconvenient embedded development system. I guess that support will come from a variety of customers including those that might otherwise look at beagle. If we don't match their convienience of use we loose critical mass of developers. If I wanted a headless system I might look at a Dreamplug and uses it eSata port for storage instead. Not being headless is a distinguishing feature for Balloon4. Why add a camera(s) and not be able to convenently view the output in real time. If I want to try Ubuntu (Unity flavour) or Wayland or OpenCV or anything else that uses opengl, not having monitor output is a big turn-off. Is Android predicated on 3D acceleration now? I doubt HTML5 codecs / flash plugins perform well over vnc. I am not making a case for lots of board real estate/power being devoted to HDMI, just to make sure we don't option out connectivity that some would regard as expected. The form it takes probably doesn't matter and off-board is fine if HDMI is needed by a product. I can easily imagine a future TCL product glued to a television with bespoke (hence Balloon4 derivative) wireless input coming from the patient. >> During development, there will always be a desktop / laptop machine >> being used for compilation, and it'll have a decent display, on which >> X works well, also serial terminals, xterms, ssh, whatever. Who really >> wants yet another monitor on their precious desk space, running scaled >> HDMI? That implies another keyboard, too. > Not if you do native development, which is what Debian and Ubuntu push > you towards and it's more and more practical as the arm hardware gets > better. Balloon4 will be at least as fast as a PC from a few years > back (pentium III?) and native dev there was no problem. > >> In short: If you want to drive an HDMI TV, a PC is probably cheaper. >> You've obviously got mains available, so you don't care about power. > Wrong. I always care about power. And so should everyone. > The power issues should be resolved at the Balloon4 derived product level (eg Challenger) and not be a design limitation surely. >> You've obviously got space available, so stick a Revo on the back of >> your TV if you want to pretend to be 'integrated'. >> If I exposed the DSS as 28 precious GPIOs on a connector, (or 24 >> GPIOs and SPI3), and let people add an HDMI chip& connector, would we >> sell any of those, ever? >> Would we sell any IO boards that sat there instead and protected >> those (1.8V) GPIO pins, and exposed them at student-friendly levels& >> connectors? > This is the real question. Is it worth the pins? I don't have an > answer to that. So long as we are happy with the answer 'go buy a > beagle if you wanted to plug it into a TV' then we don't need it. > > Ethernet and DVI/VGA/HDMI are incredibly convenient for development. > If we only provide those on a dev-board then that's OK, but lets try > not to have a 3-yr gap between board and dev-board this time in that > case. Ethernet is more important than video. > >> If DVI/HDMI over USB works as well as it seems, then why would we >> want to sit there squandering precious memory bandwidth spewing pixels >> down a wire? Plug in a display when you want to do a demo on a >> projector or something, but the other 99% of the time, run headless. DisplayLink hardware, while remarkably useable, does not survive suspend/resume (at the moment in 2.6.38.2) due to taking down USB and not re-initialising the device correctly after it is powered up. It is not a full solution. >> (The memory bandwidth issue isn't specious. 720p60 is 240MBytes a >> second, of unstoppable high priority data. Not sure if it pollutes the >> cache or not.) > If it does indeed work over USB then that's OK, (do we have 240MB/s > over USB?) And do we have enough USB sockets for ethernet, video, > serial, keyboard,? The need for a hub to do almost > anything on B3 was tiresome in practice. > >> (I'm trying to think of a time when you'd want both Balloon's FPGA >> resource, and a genuine framebuffered, pixel-painting display on a TV, >> and I can't. Something that needed the 3D graphics engine of the OMAP, >> on a projector, maybe?) Stereo cameras + FPGA CUED wizardry1 + beagle inspired TMS320 wizardry2? > I amdit I don;t understand the difference between LCD and > DVI/VGA/HDMI. Don't they all amount to "a genuine framebuffered, > pixel-painting display"? > > Any display will do, widely available ones with standard connections > are just easy to dev with. > Agreed. > Wookey NickB