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Portrait monitor support for A9home

By Chris Williams. Published: 14th Jun 2005, 10:38:21 | Permalink | Printable

First A9home specific application

Monitor in portrait and landscape modeThe pair of developers known as the SIMON team have released their first commercial application for the A9home. Published by AdvantageSix, HeadTurner is a software driver that enables users to switch to portrait screenmodes with monitors that can be arranged in wide and tall positions - as seen with Geminus and the PCI graphics card in the Iyonix.

The SIMON team is apparently named after the Silicon Motion SM501 graphics chip used in the A9home and they first appeared on the scene shortly before the Guildford show in 2004. Whilst working on the secretly guarded A9 during its development, the programmers also utilised the graphics hardware in the AGP card used in the Viewfinder to accelerate drawfile rendering.

Matt Edgar of AdvantageSix told us last night that all the team's work is related, despite the differences in the Viewfinder's ATI card and the A9home's Silicon Motion chipsets. He said, "The hardware abstraction in RISC OS 4 is very valuable. It benefits everything in the long run."

The major difference between the Nvidia PCI card in the Iyonix and the embedded chipset in the A9home, is that the datasheets and programming details for the SM501 are available for anyone, making it more likely that the full potential of the chipset can be used - from 2D acceleration to support in hardware for DVD playback.

RISCOS Ltd.'s Paul Middleton added in the HeadTurner announcement, "The future power of RISC OS is very dependant on harnessing the rapidly evolving capabilities of graphics hardware. Partnerships between developers in the RISC OS world to accomplish this are echoing those between ARM and graphics hardware in the wider world."

The A9home is currently nearing the end of development and is available only to third party developers who wish to beta test the product. According to Matt, Ad6 wants to keep the number of people with a machine to a manageable number in case someone discovers a hardware bug and the units have to be recalled for a fix: recalling hundreds of machines this early would prove costly.

The A9home with HeadTurner will be demonstrated tomorrow evening at the RONWUG usergroup.


AdvantageSix HeadTurner details

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While understanding the problem of RBG sequence is it possible for the Iyonix to have access to this even if you needed to buy another video card? (one that has its specs available

 is a RISC OS Userrmac on 14/6/05 11:10AM
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Not unless you can find a way to run the card's (x86) boot ROM code, or initialise it in exactly the same way using ARM. Normally, such things are very hard to come by.

 is a RISC OS Usermrchocky on 14/6/05 11:36AM
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Chocky: Simtec's ABLE and Xfree/Xorg have an x86 emulator in them for precisely this purpose. Normally it only need be a real mode x86 emulator, so there's not actually that much to do. Well, there is, but it's certainly not as bad as it might be.

 is a RISC OS Usernunfetishist on 14/6/05 12:20PM
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There are various solutions, I didn't really want to go into the detail of them here. Simtec's is of course largely desiged to deal with the hardware they provide, and may or may not be suitable for an abitrary card, and they may also be performance issues. Other solutions have been employed under Mac OS and indeed, the Iyonix.

 is a RISC OS Usermrchocky on 14/6/05 1:13PM
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One thing stull puzzles me. According to the SM501 datasheet the maximum screen resolution supported is 1280 x 1024 and yet the A9home can display 1600 x1200. How?

 is a RISC OS Usermripley on 14/6/05 1:27PM
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chocky: "designed" "arbitrary" Actually, I believe it is designed for any card you want to use, within reason. (For CATS and such, where you can plug a PCI VGA card in, run Linux, etc.) Once you've run the BIOS, which you only need to do once, you can use a native driver, use it in VESA mode, and such. So it's not as if everything you do with the video has to go through the emulator.

I have no idea how Mac OS and the Iyonix do it, be it via a small emulator, or by rewriting the BIOS in the native instruction set. Care to enlighten us if you know?

 is a RISC OS Usernunfetishist on 14/6/05 1:48PM
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mripley: Have Advantage Six actually confirmed the chipset yet? If the idea that it's using the SM501 is speculation, then perhaps one of the two pieces of incompatible knowledge you have is false.

 is a RISC OS Usernunfetishist on 14/6/05 1:53PM
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It's good to see developments for the A9Home even before it's been fully released! The creation of a 'new' RISC OS development team is also encouraging.

But why the secrecy over who SIMON are?!

 is a RISC OS Userflypig on 14/6/05 1:58PM
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It's not me.

 is a RISC OS UserSimonC on 14/6/05 2:23PM
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If the use of SM501 is speculation then I think Drobe should stop referencing it in their articles or at least remind the reader that it is still speculation. Anyone reading the above article in isolation would think that the use of the SM501 is fact.

 is a RISC OS Usermripley on 14/6/05 3:12PM
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Just to clarify: it is fact. Matt@STD confirmed last night over the 'phone that the A9 is powered by the SM501 and the S3C2440, after a number of sources pointed it out.

The resolution issue is probably best explained by Ad6. A member of the Simon Team told me that they are capable of driving a CRT at the resolution shown in the FAQ.


 is a RISC OS Userdiomus on 14/6/05 3:30PM
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Just speculating... if the SM501 can drive a monitor (didn't find on the datasheet if CRT and/or LCD) to a max of 1280x1024 and Ad6 confirm that A9 can display 1600x1200, the only thing I could think of is a sort of "Eigen-factor" trick like that allowed RiscPC to have very high resolution displays even with 1MB VRAM.

 is a RISC OS Userbernie on 14/6/05 5:05PM
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As far as I can remember, the eigen-factor 'trick' didn't let the Risc PC have greater resolutions than could be stored in VRAM. It just let you trade extra horizontal resolution for less vertical resolution (or vice versa). Although the workspace applications worked in was in a higher resolution than was displayed, this has always been the case right back to the BBC micro days.

 is a RISC OS Userninja on 14/6/05 5:36PM
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This is also speculation but...

I suspect the difference between Ad6's claims and the datasheets is simply to do with the word "supported". Silicon Motion say the higher resolutions are not supported, but (maybe) this doesn't mean they're not possible. The difficulty of obtaining higher resolutions probably has more to do with timings than to do with video memory size (the A9Home has 8Mb VRAM which is sufficient for 1600x1200x32bit). Pushing the chip to 1600x1200 may be possible, but may not be within the timing specifications of the SM501 hardware.

But in case there's any doubt, I *am* making this up as I go along.

 is a RISC OS Userflypig on 14/6/05 5:52PM
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In reply to flypig and bernie:

The datasheet tells us that the digital output (DVI) is limited to 1280x1024. IIRC this corresponds to the original DVI specs and only recent PC graphic cards offer the new higher spec DVI interfaces.

 is a RISC OS Userandretim on 15/6/05 8:01AM
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The DVI spec 1.0 specifies at least one 10bit TMDS link operating at up to 165MHz giving 1.65Gbps of bandwidth. This provides for 1920x1080@60Hz to 1280x1024@85Hz... including 1600x1200@60MHz with GTF blanking. This readily explains the conundrum - the datasheet states the recommended resolution for a CRT with an acceptable refresh rate, while Ad6 quote the maximum they could get working with a CRT - acceptable to the user or not.

I hope, of course, that this isn't the explanation!

 is a RISC OS Usersenduran on 15/6/05 8:12PM
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Ahem. 1280x1024@85Hz ... including 1600x1200@60Hz

 is a RISC OS Usersenduran on 15/6/05 8:14PM
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Well, 1600x1200@60Hz is fine. Every TFT monitor I have seen that could display this resolution could do so without flicker at 60Hz.

 is a RISC OS UserJGZimmerle on 15/6/05 8:23PM
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The explanation given at RONWUG tonight is that the datasheet isn't completely up to date, and the chip has moved on a bit since then (e.g. the "this information is subject to change without notice" part at the start), and the limiting factor in the A9home is the amount of VRAM.

 is a RISC OS UserSimonC on 15/6/05 10:13PM
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Yes, LCD monitors don't flicker at 60Hz; my point was that Ad6's claim was with a CRT where flicker would be unacceptable.

In any case Stuart Tyrrell just emailed me to say that they haven't just quoted 'the maximum they could get working with a CRT - acceptable to the user or not', so it seems my guess was as off-track as everyone elses. Stuart seemed concerned about being misrepresented but foolishly chose not to post here and stop rumours that would hurt his buisiness. I suppose that leaves me to do him the favour!

 is a RISC OS Usersenduran on 15/6/05 10:15PM
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I saw 1600 x 1200 x 16M on a CRT screen at RONWUG with no trace of a flicker.

And the HeadTurner demo was impressive.

 is a RISC OS Userjc on 16/6/05 12:02AM
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What refresh rate was it running at?

I have incredibly sensitive eyes. I've often pointed out flicker on CRT monitors when others have been oblivious.

 is a RISC OS Userfylfot on 16/6/05 12:17AM
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fylfot: I think it was 60. Matt did say that it came in just under the limit for the 8MB VRAM so anyone care to do the arithmetic? [mine doesn't work properly after midnight...]

 is a RISC OS Userjc on 16/6/05 12:25AM
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The refresh rate was 60 and there was "no trace of a flicker"? Hmm, you must be one of the oblivious I mentioned. ;)

It looks like I'll have to get an LCD monitor if I purchase the A9home.

 is a RISC OS Userfylfot on 16/6/05 1:54AM
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In reply to fylfot & senduran: It's a big LCD to use 1600 x &c! And how much desk-space is the CRT taking up that uses the same resolution? ;-)

As I understand it the A9 produces a resolution beyond what is generally used and well within the specs of the chips. Not an issue. After last night's demonstration I'm just quibbling with myself between getting a monitor that turns or fixing my LCD to the wall in portrait mode. ;-)

 is a RISC OS Userjc on 16/6/05 10:52AM
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Looking around at LCD monitors. Ones that can cope with 1600 x 1200 as their native resolution are about 21".

 is a RISC OS Userfylfot on 16/6/05 12:46PM
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When an LCD spec states a native resolution, does that imply the maximum resolution, or can the monitor be driven higher than that.

 is a RISC OS Userdemondb on 16/6/05 1:25PM
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to fylfot: "The refresh rate was 60 and there was 'no trace of a flicker'? Hmm, you must be one of the oblivious I mentioned." Maybe it's old age; there has to be some compensation in addition to wisdom. ;-)

to demondb: I think monitors can appear to drive resolutions higher than their capability by throwing away information or averaging. I'm sure that some people think they are viewing higher resolutions than is fact and they are simply looking at a larger area at a lower quality. Unless you want to view monitors at a distance - and why would you unless you have an audience - 21" LCD seems to me to be larger than the vast majority of users need. I don't say want as there is always pressure for bigger is better; surely something that is contrary to the concept of our subject in this discussion!

The HeadTurner software makes possible the use of smaller screens to match the A9 whilst still being able to see a whole A4 page on screen at once and edit the contents. Any suggestions for small screens that can be viewed in portrait mode? In A9 blue?

 is a RISC OS Userjc on 16/6/05 2:07PM
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What psudeotechnical rubbish is this? How do you sleep at night fobbing of this stuff as reliable information?

It really is tiresome having to deal in a market where there are (even a very small number) or people actively spouting unsubstantiated and made up factoids.

RISC OS doesn't need developers. It has John Cartmell, keeper of all wisdom.

The stuff John's been saying of the last few days really is shocking, and I can't endorse any of it, and it continues to amaze me that anyone bothers when they have to fight upstream against this.

The only silver lining is that I know most users by now can spot John for the nutcase that he is, and safely ignore him.

Mod me up or down as you wish, but this is not acceptable behaviour when RISC OS has fought so hard the last few years against misinformation.

 is a RISC OS Usermrchocky on 16/6/05 3:27PM
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mrchocky: The appropriate comment is a simple correction. I don't pretend to your technical capability but your communication abilities outside that area is zero. Whilst I give information that is capable of being tested and refuted you have added no information to the debate - just another dollop of ill-feeling.

 is a RISC OS Userjc on 16/6/05 3:49PM
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This doesn't occur that often, but I agree with Chocky, although I wouldn't have used such strong terms. While I've not read much of John's postings elsewhere, the ones here seem to appear to have a pythonesque surrealism about them, and are rarely based in fact, but more bias and blinkered madness. Strange.

 is a RISC OS Usernunfetishist on 16/6/05 3:53PM
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I think what John was trying to say is that if you're editing a document, for example, in portrait format, you'll be struggling a bit for usable screen space on a small monitor - expand it to fill the width then you don't see that much of the height, or view a decent height of document, but everything on it is tiny. Rotating everything by 90 degrees, so the aspect ratio of the monitor is a better match for the document gives a better use of the available screen space, which is why the Headturner software (or Geminus on the Iyonix, or presumably equivalent things on other systems) helps with small screens, not by somehow conjouring up extra pixels from thin air.

 is a RISC OS UserSimonC on 16/06/05 4:13PM
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John: Once again you respond with hypocrisy.

You question my communication skills, yet it is _you_ who is communicating misinformation, and things you simply cannot back up or provide references to.

You accuse me of creating ill-feeling but again fail to recognise that it's your own actions here that are at fault. You're trying to pass the buck by suggesting I should provide a correction.

In fact, I'm not going to - my knowledge of these things is inexact, and I would spend a bit of time researching it before I tried to say anything authorative on the topic.

No John, your behaviour is unacceptable. Trying repeatedly to implicate me because I'm the one pointing it out is disingenous. Take some responsibility for your actions. If you can't back up what you're saying, then for goodness sake, shut up.

 is a RISC OS Usermrchocky on 16/06/05 4:23PM
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Peter Naulls and Rob Kendrick: I've read my comments again and I'm afraid that I cannot locate the errors that you appear to have identified. Most of what I have said are simple observations that are confirmed by others or value judgements of my own that whilst you can obviously disagree with them you certainly cannot say that my value judgement is wrong. Would either or both of you like to point out the mistakes that you have discerned?

 is a RISC OS Userjc on 16/06/05 4:26PM
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to Simon: Exactly that. When editing pages on my current monitor I cannot see the letters clearly enough and view the whole page at the same time. With HeadTurner/Geminus I would be able to do both without the problems of a larger screen (cost/space). Unless you're looking at a double-page spread you waste lots of space when DTPing a portrait document on a landscape monitor.

 is a RISC OS Userjc on 16/06/05 4:32PM
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Or course you can't; you made no effort to back up anything you said with references. As usual. Why should we go to the trouble if you don't?

 is a RISC OS Usermrchocky on 16/06/05 4:33PM
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Whats this averaging thing JC is on about?

I paid 1000s to get a 20" LCD that did 2048x1536 & It has 2048 pixels horizontally & 1536 pixels vertically...

...didn't I?

 is a RISC OS UserROHC on 16/06/05 4:37PM
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Keith: Yes. And I'm not about to start counting the 1600x1200 pixels on my 21.5" CRT, either.

 is a RISC OS Usernunfetishist on 16/06/05 4:48PM
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Just trying to sort things... demondb: AFAIK, native resolution of a LCD is a 1:1 match with pixels on the screen. So, native resolution of 1024x768 means that the LCD is made with a grid of 1024x768 pixels, and that's the maximum resolution of the panel. Lowering the resolution means applying a rescaling algorithm to the image, with the effect of 'blurring' details. As stated on some sites, it's best to buy a LCD with the native resolution you plan to use the most of time. JC: I don't think a CRT monitor can display more than the max resolution for what is made. In fact, I noticed that when changing resolutions on other machines/OS, a message says "going outside specifications of your monitor could seriously damage it" or sort of.

 is a RISC OS Userbernie on 16/06/05 4:57PM
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Keith & Rob: I said "I think monitors can appear to drive resolutions higher than their capability by throwing away information or averaging. I'm sure that some people think they are viewing higher resolutions than is fact and they are simply looking at a larger area at a lower quality. "

For the first part - what happens if you implement a resolution greater than the pixcels available? AFAIK this is accepted by some monitors. If they don't throw away information or average it in some way - then what do they do? As for the second: my reference to *some* people may well not refer to you. I presume that you purchased monitors that would make full use of the information that you threw at them.

As you have both kindly confirmed though the size (and price) of your monitors does not balance well with the much lower price and size of the A9 computer. Finding ways of making best use (eg using HeadTurner) of a smaller and cheaper monitor would seem to be appropriate.

 is a RISC OS Userjc on 16/06/05 5:04PM
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Actually, my monitor cost 40 off eBay.

 is a RISC OS Usernunfetishist on 16/06/05 6:36PM
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jc>"what happens if you implement a resolution greater than the pixels available?"

You can't (the monitor will object if you try to use a scanning frequency higher than it can support [Think of Scotty saying "Capn ye canna break the lawwss of Fisicks"]). If it *could* be run as if to display a higher resolution image you'd run up against the Nyquist Sampling Theorim, you'd get aliasing (fringe effects called moire fringes caused by trying to display too complex an image with too few sample points (pixels)), the only solution - use a low pass filter to remove the higher frequency components - the end result is you get an image that fits your monitor but has been heavily filtered so that it is blurrier than the equivalent would be on a monitor that *did* support the resolution you requested (in short what's the point).

As someone else said best get a monitor that supports the resolution you intend to use.

 is a RISC OS UserAMS on 16/06/05 8:31PM
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jc: "It's a big LCD to use 1600 x 1200!"

There was a 19"er that did it, but typically you find this resolution at 20.1" and higher. No, that's not big. My 21" LCD is only 2" wider than my 17" CRT and 9" less deep. If comparing to another LCD surely the A9 being so small means you now have extra desk space for a larger monitor?

"As I understand it the A9 produces a resolution beyond what is generally used and well within the specs of the chips. Not an issue."

I've heard no claim that it produces beyond 1600x1200, and if you're saying that 1280x1024 (next lower common resolution) is 'beyond what is generally used' you're mixing things up. If 1280x1024 or lower is in common use it is because people are using ancient computers not capable of higher. They aren't willing to pay for a viewfinder or upgrade to an Iyonix, but a cheaper computer finally able to display modern resolutions (that everyone outside the RISC OS community enjoys) would be ideal. This rather breaks down if the new cheap computer doesn't actually do what its designers say it does in an acceptable way (1600x1200 on a CRT over 60Hz), which is what we were confused about.

Why not be helpful and encourage Stuart Tyrrell to reveal the refresh rate at 1600x1200 and then we can all be happy and just look forward to the machine's release.

 is a RISC OS Usersenduran on 16/06/05 8:51PM
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My experience has been that many people are not happy with resolutions beyond 1280x1024. This constantly amazes me at work, where I have my computer set to run at 1280x1024 and everyone complains that they can't read the text (WinXP & 17 inch monitor). If people want higher, they tend to use two monitors side by side.

Possibly the people on these forums are more discerning than the average user, but I don't think the claim that 1600x1200 is higher than most people use is too unreasonable. Nonetheless, I'd expect any good modern computer to be able to cope with it.

 is a RISC OS Userflypig on 16/06/05 9:19PM
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In reply to Sendu:

I disagree with your views on resolutions. With a RPC and a dual-head VF card I'm running 2x 1024x768 each displayed on a 19" LCD. If I increase the resolution all that happens is that the icons & text displayed gets too small to read easily unless I always have my glasses on AND sit much closer to the screens.

A problem with RO is that if you use high resolutions, although some apps will let you scale their displays, eg NetSurf, OvationPro... other apps don't let you do so. If you pick a bigger desktop font then many apps don't have sufficient space in their dialogboxes to display the full text for fields.

 is a RISC OS UserJNicoll on 16/06/05 10:10PM
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One of the improvements that was introduced in RISC OS 5 is a new mode style with eigenvalues set to zero (EX0 EY0). This doubles the size of icons and text as you would normally have them, and uses very high resolution icons. This might possibly solve the problem you have with higher resolution modes under RISC OS (I'm afraid I don't know if it's part of OS 4 or not though).

Unfortunately I don't have a good enough monitor to properly make use of it :(

 is a RISC OS Userflypig on 16/06/05 10:22PM
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Sendu: I know it got lost in all the irrelevancies but I did give the refresh rate: 1600 x 1200 x 16m @ 60Hz. It's limited by the VRAM. We had half a dozen A9s running networked last night. One using a rotatable monitor and demonstrating the 4 positions of HeadTurner - and one on a (very heavy!) CRT monitor capable of 1600 x 1200 - with a mix of others. If Danny had remembered to recharge the batteries for his camera you could have had photos! To me the display on the CRT was rock steady and no one else complained that I heard. 1600 x 1200 is beyond what is generally used and to ask more of an entry level machine seems to be excessive - aspecially as that might require the purchase of a monitor costing far more than the computer itself. With the A9 I might move up to using 1280 x 1024 ;-)

 is a RISC OS Userjc on 16/06/05 11:01PM
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jc: You said you /thought/ it was 60Hz, and after Stuarts email I rather assumed I was wrong about it being 60Hz. If I was correct, evidently Stuart likes sending people pissy emails for no particular reason :/

 is a RISC OS Usersenduran on 16/06/05 11:21PM
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Sorry to inject some facts here:

Refresh rate is normally limited by the monitor/video chip cominbation. The VRAM has nothing to do with it. That limits the colours and resolution combination.

1600x1200 is easily handled by any 17" CRT made in the last five years. Certainly excellent monitors like the Iiyama 410 can be picked up second hand for as little as 5UKP since people are upgrading to LCDs and can do that up to ~75Hz. Much lighter monitors such as later Iiyamas like the 450 can be picked up for well under 50UKP can include a USB hub to boot.

Plenty of people use 1600x1200, and plenty also use what is usually one step down from that, 1280x1024. To say 1600x1200 is "well beyond" would be wrong.

I've not seen anyone claim that the A9 was an "entry level" machine until now, and there's no particular reason to think so, except to slot into your unrealistic view of a range of RISC OS machines.

 is a RISC OS Usermrchocky on 16/06/05 11:24PM
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JNicoll, flypig: Yes, I take what I said back; 1600x1200 is beyond what most people use simply because most people with newish computers are probably using 15-19" LCDs with resolutions of 1024x768 to 1280x1024. Most people with CRTs probably have ones that are only capable of up to 1280x1024 at reasonable refresh rates as well.

Anyway, 1600x1200@60Hz is perfect for a 20+'' LCD (pity no DVI output unless I missed a spec). My only query remains 1600x1200 on a CRT which at 60Hz wouldn't be acceptable to most people - if the designers are going to say it does something in their FAQ they ought to be completely honest about it and not mislead people who might have CRTs capable of 1600x1200 at high refresh rates.

 is a RISC OS Usersenduran on 16/06/05 11:38PM
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mrchocky: Could you check your facts and supply some references please? A quick look at Iiyama's website ( [link] ) showed only 2 17'' monitors and they both have a 'maximum resolution of 1280x1024@65Hz'. If they can be encouraged to get to 1600x1200 the refresh rate would be truly terrible. The story is very similar over at Viewsonic ( [link] ) where the max a 17'' does is 1280x1024@66Hz. The recommended resolution for 'flicker free' operation of these monitors is 1024x768.

Going up to a 19'' CRT tells a different story however, and this is where you'd really want to know if the A9home can do your monitor justice.

 is a RISC OS Usersenduran on 16/06/05 11:48PM
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Sendu: Try a babelfished version of iiyama.ru: [link] 410%2Findex.shtml It appears details of the VisionMaster Pro 410 have been purged from .com and .co.uk (most likely because they're no longer available new)

 is a RISC OS Userjmb on 17/06/05 01:54AM
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Bah. Please fix the URL parser, drobe, ta ;)

Take 2:

[link] %2Fpro%34%31%30%2Findex.shtml

 is a RISC OS Userjmb on 17/06/05 01:58AM
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jmb: Thanks. So when Peter says "1600x1200 is easily handled by any 17" CRT made in the last five years" what he actually means is it can be handled by a small handful of premium 'pro' series monitors that were released /more/ than five years ago and are no longer produced. Ok. I'll try and avoid Peter's fact needle in future ;)

 is a RISC OS Usersenduran on 17/06/05 08:12AM
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AMS: resolution greater than the pixels allow. Some displays certainly permit this. (We have 800 x 600 projectors at work that will display 1024 x 768) yes they do look horrid because information is dropped (how horrid is a personal opinion, some people hate the display, to others it is still acceptable). Averaging blocks of adjacent pixels would reduce the definition to match then native resolution . Low pass filtering is not enough, because that will only have an effect horizontally, (ie whole lines would be dropped, giving aliasing effects.)

John's original statement was valid and anyone who disagrees should take time to properly familiarise themselves with sampling theory and then re-read what he put carefully.

 is a RISC OS Userjess on 17/06/05 08:51AM
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Not at all, that's a strange use of logic. I agree that "any" was used in haste, but Iiyama's current 17" offerings really are at the very bottom of the budget range, and their limitations aren't very surprising with manufacturers focusing much more on LCDs plus the push for very cheap PCs.

Avoiding this very low end of the market, somewhere like froogle reveals plenty of cheap monitors that can do 1600x1200 starting at around 65UKP.

My specific mention of the 410 and 510 was because they were monitors I am familiar with, and they still remain some of the best CRTs you can get, and certainly can be picked up much more cheaply than the cost of the computer. The salient other point you've picked is that LCDs are usually much more acceptable at low refresh due to persistence than CRTs, although I do know people who insist that they don't mind 60Hz on a CRT in the right lighting conditions.

 is a RISC OS Usermrchocky on 17/06/05 08:54AM
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Jess: no, John's statement was at best, vague hand waving, even though it might have been distantly based in fact. Other comedy comments confirm that he really isn't in a position to be making such statements.

He didn't name any specific examples such as you've done, and I don't believe (someone correct me if I'm wrong) that what occurs in LCD projectors is common for normal displays, although they may well do the reverse and fill in gaps to make a smaller resolution scale to fit the entire display.

Again, I am hesitant in making such comments as I freely admit that my knowledge of LCDs is far from comprehensive.

 is a RISC OS Usermrchocky on 17/06/05 09:04AM
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John was trying to make the comment in non-techie terms. [Ideally, I think he should have explicitly stated "some monitors" and used the word display, rather than drive.]

I certainly think you are correct that most LCD panel displays will not attempt to display scan rates outside those expected to be able to display natively. (I say expected, because if you double the horizonal clock rate as in the rectangular modes, eg 2048 x 768, they should still display it and drop information by averaging or dropping pixels).

I would however be very surprised if there an /no/ consumer LCD panels that behave like the projector (some small LCD panels intended for equipment racks certainly do, and obviously small LCD TVs do too) .

I also think it is probably better to dispute earlier comments directly rather than "by proxy" .

 is a RISC OS Userjess on 17/06/05 09:53AM
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I always use 1600x1200 or higher both at work and at home and would not go lower, just can not fit a couple of pages of text or a couple of web pages on the screen otherwise, I use at both places a 19"crt, would love a 20"+ lcd to save space but that will have to wait until prices come down a bit.

 is a RISC OS UserPete on 17/06/05 09:57AM
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I should point out that the Iiyama 450 I mentioned earlier is in fact a 19", not 17", but might be a natural choice for someone looking for a CRT able to do this resolution.

 is a RISC OS Usermrchocky on 17/06/05 10:14AM
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The little 15" Sony LCD monitor that I'm thinking of replacing for something bigger will certainly attempt to display things greater than the actual number of pixels (1024 x 768), but as expected, the quality isn't up to much because it's having to drop some pixels somewhere. I don't think it filters, just drops. Some lower resolution modes also get scaled (common ones like 800 x 600), and they look even worse, with having to use two lines of pixels sometimes and one at others. Obscure (from the monitor's point of view) modes just got shrunk to plotting the actual number of pixels.

Jess: There's no reason you couldn't low pass filter both horizontally and vertically, unless you're talking about operating directly on the analogue signal, and not the actual image. I suppose the graphics card in new machines could be made to do this, and output an image to the monitor at the resolution it expects.

 is a RISC OS UserSimonC on 17/06/05 10:55AM
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to Jess: You are quite correct. I certainly intended to refer to 'some' rather than 'all' monitors in my original comment. In everyday English that was the meaning of what I wrote! ;-( And thanks also for clarifying the matter about averaging or dropping pixels. I hadn't tried it myself but had heard that it could happen and have seen displays described as far higher resolution than the evidence to my eyes.

All a massive red herring of course - and I have no idea what the 'earlier comments' might have been. The disputed matter was whether the A9 can display 1600 x 12000 x 16m and it can. I assume that's the maximum but it's still only a development machine.

 is a RISC OS Userjc on 17/06/05 11:03AM
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Does it have a DVI output, or are all the DVI comments just about the capabilities of the chip?

(And OT does it support big Wimp slots like RO 5?)

Simon: Yes, I should have said simple low pass filtering.

 is a RISC OS Userjess on 17/06/05 11:19AM
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In reply to Jess:

The A9home (developer edition) does ot have any DVI output. Only standard VGA.

 is a RISC OS Usersa110 on 17/06/05 2:40PM
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That's a big shame. DVI and select are the two things i want on my Iyonix, if / when they appear the combined cost would be halfway to the cost of an A9home, which would have been a tempting alternative to waiting.

 is a RISC OS Userjess on 17/06/05 10:42PM
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