Custom VGA output : what resolutions are expected to work?

Question

I am thinking of creating a device which displays graphics and animation to generic computer display with 16:9 aspect ratio via analog interface (D-sub).

The question is which resolutions are guaranteed to work on most monitors?

Obviously, standard HD and fullHD likely to work (1280x720 and 1980x1080), but how about more exotic 768×480, 960×540, 1024×576 - can I expect that they would work on most of more-or-less modern HD-capable monitors?

FullHD and HD have too high pixelrate and require too big frame buffer for my hardware hence my interest of smaller resolutions.

Unfortunately this is more a case of researching graphics and standards (and there are a lot of them) than an EE design or technical question. See http://en.wikipedia.org/wiki/Graphics_display_resolution for a list of resolutions, but I wouldn't begin to speculate on what's considered standard, let alone what "most" monitors support. — JYelton, Dec 12 '12 at 02:34
Worth pointing out that it it doesn't do something sensible with 640*480 you can't really call it VGA, and a lot of boot programs or BIOS setup systems won't know what to do with it... — , Dec 12 '12 at 10:09
Brian, I am not talking about PC screen resolution. Video signal will be generated by FPGA. — BarsMonster, Dec 12 '12 at 10:49
@JYelton Yes, I've seen this list. But unfortunately speculation based on practical experience of designing hardware with VGA output is what I need. — BarsMonster, Dec 12 '12 at 10:51
What resolutions are expected to work? All of them! Which ones will work? Well, that depends... — , Dec 14 '12 at 17:23
As this isn't really electrical engineering, I think superuser would be a better place for this question. Also, not even the standard resolutions work an all monitors even if they can handle higher resolutions. — Gunnish, Dec 14 '12 at 17:50
Most flat panel type displays sample and interpolate the input signal, so they are potentially much more flexible than multisync CRTs where, though there are likely limitations as to what they will accept. Also, you need to be concerned not only with resolution, but also with framing/dead area - again, modern displays will sample and correct to a large degree, but there have to be ultimate limitations. — Chris Stratton, Dec 14 '12 at 18:57
Most modern LCDs will show any resolution you throw at them (as long as they are within the monitor's spec). — Renan, Dec 14 '12 at 20:41
@Renan But what are generic limitations? Can I throw 240 scan lines for example? — BarsMonster, Dec 15 '12 at 01:16
I think you'd have to check the manual of the monitor to see what it supports. — Renan, Dec 15 '12 at 01:19
@Gunnish: This seems the proper forum. The question is essentially, "I want to design a device that will output VGA-style video and produce the best possible display with a typical monitor chosen at random; what sorts of scan/pixel rates, or what other techniques should i use, should I use to get the best results with typical monitors." — supercat, Dec 16 '12 at 20:35

jippie · Accepted Answer · 2012-12-16T11:44:14.320

The question is not so much about what resolutions a monitor should support, the question should be about how to get a report of supported screen modes from the monitor to the PC. The monitor 'tells' the PC what modes are supported through I²C and the PC has to deal with that.

On Linux this looks like (notice I have 2 monitors attached):

€ xrandr
Screen 0: minimum 320 x 200, current 3200 x 1080, maximum 8192 x 8192
VGA1 disconnected (normal left inverted right x axis y axis)
HDMI1 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 510mm x 290mm
   1920x1080      59.9*+   60.0  
   1680x1050      59.9  
   1680x945       60.0  
   1400x1050      59.9  
   1600x900       60.0  
   1280x1024      75.0     60.0  
   1440x900       75.0     59.9  
   1280x960       60.0  
   1366x768       60.0  
   1360x768       60.0  
   1280x800       74.9     59.9  
   1152x864       75.0  
   1280x768       74.9     60.0  
   1024x768       75.1     70.1     60.0  
   1024x576       60.0  
   800x600        72.2     75.0     60.3     56.2  
   848x480        60.0  
   640x480        72.8     75.0     60.0  
   720x400        70.1  
DP1 disconnected (normal left inverted right x axis y axis)
HDMI2 connected 1280x1024+1920+0 (normal left inverted right x axis y axis) 376mm x 301mm
   1280x1024      60.0*+   75.0  
   1280x960       60.0  
   1280x800       74.9     59.9  
   1152x864       75.0  
   1280x768       74.9     60.0  
   1024x768       75.1     70.1     60.0  
   1024x576       60.0  
   832x624        74.6  
   800x600        72.2     75.0     60.3     56.2  
   848x480        60.0  
   640x480        72.8     75.0     66.7     60.0  
   720x400        70.1  
DP2 disconnected (normal left inverted right x axis y axis)

Unfortunately for this question I have only HDMI attached monitors, but classic VGA monitors talk back to the PC too when attached through 15 pin sub-D. Check DDC (Display Data Channel) on Wikipedia

Actually with --verbose flag you get all sorts of cool details but that is way beyond the scope of this question.

640×480 is a safe bet for all VGA monitors. So is 800×600 and most of the time 1024×768.

score 0 · Answer 2 · answered Dec 14 '12 at 17:37

0

There's a list of standard and common modes on the Wikipedia Vesa Bios Extensions page.

answered Dec 14 '12 at 17:37

shuckc

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Custom VGA output : what resolutions are expected to work?

2 Answers2