QXGA LCD Panels now cheap ... good enough for variable resolutions?

Stumbled upon this coincidentally: https://classifieds.ksl.com/listing/58327699
Same one?

@jessenator  Nope, that's the MXP model or whatever it's called.  I thoroughly searched the user manuals for various different NEC models.  That one doesn't have the Expansion feature that I want.  It only has the usual adjustments for Clock, Phase, and Vertical/Horizontal movement.  But nothing for scaling.  Seems like NEC had a very select range that supported the Expansion option.

The SONY LMD-1950MD led me down a tangent for Medical Displays.  I found several GE USE1913A monitors, but I could NOT find manuals. They were bundled with patient monitoring systems, and the manual for that device didn't cover the OSD controls for the display itself.  So I have no idea if the GE Medical Display would suit my purposes.

Wouldn't mind knowing since there are a bunch of them on eBay for relatively cheap.  I may have to fall back on the Black NEC, but was hoping for a nice white, beige, or platinum colored panel to match my computer.

olePigeon said:

After many, many hours of searching, I finally found an LCD display that should work.  The NEC LCD2090UXI is a 20" 1600x1200 display that offers:

• EXPANSION: Selects the zoom mode.
  
• FULL: The image is expanded to 1600 x 1200, regardless of the resolution.
  
• ASPECT: The image is expanded without changing the aspect ratio.
  
• OFF: The image is not expanded.
  
• CUSTOM: Refer to the ADVANCED OSM Controls section of this user’s manual for detailed instructions.
  

So that's exactly what I'm looking for.  Now to see if I can find one or one that's equivalent.  A 1600x1200 display would be pretty sweet.  Only concern I have is whether those options are available over VGA and not just DVI.

Click to expand...

T85A (AKA  part # 9519-AW1 ) from IBM has this feature.   It can display resolutions as either expanded to full LCD resolution, or just fill the pixels on teh screen that correspond to the original resolution.   It only goes up to 1280 X 1024 though.

I'm not sure if it has the "ASPECT" feature listed above though.  Or put it another way, I know it has either ASPECT or FULL, I'm not sure it has both.

olePigeon said:

NEC LCD1980SX.  Man that's a nice looking screen...

View attachment 30471

Click to expand...

A word of warning: Those NECs mentioned above are a decade and a half old now. I have one of the 20" 1600x1200 ones in the garage that I trashpicked because, yeah, at first glance it looked awesome featurewise, but it didn't take me long to realize that there has been a *lot* of water under the LCD monitor bridge since those were made. Not only is the "best case" color reproduction and contrast of the LCD not that great, there's a good chance that a used one has a *lot* of miles on the old CFL backlight. I would strongly recommend seeing a monitor of this age in person before ponying up any money for it. There's a fair chance the display will leave a lot to be desired.

@trag 1280x1024 is perfect.  Unfortunately that model IBM panel appears to be pretty rare.

@Gorgonops  I get what you're saying.  I'd get a brand new monitor if I could find one that supports those features.  Right now I'm just going through eBay looking at every single 4:3 and 5:4 monitor and Googling for the manual.  I'm hoping maybe I'll be able to find a new one.

Edit:  It's only on their widescreen displays. :/

Custom Scaling (select models) Selects the method on how displayed information on the monitor will be formatted. Select:

• Fill to Screen - image fills the entire screen and may look distorted or elongated because of nonproportional scaling of height and width
  
• Fill to Aspect Ratio - image is sized to fit the screen and maintains proportional image
  
• One-to-one - disables video scaling, displays an image that is smaller in size than the monitor’s capability and centers the image on the screen in the active viewing area
  

I'm thinking that perhaps having a small database of LCD monitors that support this feature would be useful to not just Mac users but any vintage computer user who wants 1:1 pixel mapping on a monitor.

I wonder if searching for an LCD controller from the PiVerse with these features might be taking a look? Might, retrofitting just about any LVDS panel display with a more capable controller be a way go?

olePigeon said:

@trag 1280x1024 is perfect.  Unfortunately that model IBM panel appears to be pretty rare.

Click to expand...

Yeah, after they cleared out from their first use owners, they seem to have disappeared from the market.

There was one reseller who had stock, but they seem to have run out a couple of years ago.  

I picked up a few of them for a song (compared to new LCD prices at the time) several years ago.   Feature-wise, they are fantastic.  Also, brightness is very even, but dimmer than new LCDs.  

I may pick out the runt of the litter and try replacing the backlight tubes on it and see how that goes.

I'm kind of surprised that the One to One feature is so hard to find, given how common it was in teh early days of LCDs.   I guess there was more need then to support older resolutions.

Newegg often has refurbished 1280 X 1024 LCDs from HP and Dell for about $50 each.   It might be worthwhile to check the manuals on those models.

https://www.newegg.com/dell-p1914s-19-sxga/p/N82E16824260224

https://www.newegg.com/p/0JC-0004-00HW5

https://www.newegg.com/hp-la1951g-19-sxga/p/N82E16824276607

That last one is $90, but I've seen it on sale for about $50.

trag said:

I may pick out the runt of the litter and try replacing the backlight tubes on it and see how that goes.

Click to expand...

I was parting out a 17" display just to be rid of it because it was too dim.***** All I wanted were the speakers, but it turned out the backlight sheeting was fine. Could adaptation/cannnibalization be reasonably straightforward in your case? I've always wondered if those sheets could be cut down from two sides and retain function of the reduced size panel?

olePigeon said:

Edit:  It's only on their widescreen displays. :/

Custom Scaling (select models) Selects the method on how displayed information on the monitor will be formatted. Select:

• Fill to Screen - image fills the entire screen and may look distorted or elongated because of nonproportional scaling of height and width
  
• Fill to Aspect Ratio - image is sized to fit the screen and maintains proportional image
  
• One-to-one - disables video scaling, displays an image that is smaller in size than the monitor’s capability and centers the image on the screen in the active viewing area
  

I'm thinking that perhaps having a small database of LCD monitors that support this feature would be useful to not just Mac users but any vintage computer user who wants 1:1 pixel mapping on a monitor.

Click to expand...

Check out the specs of the HP PL766A I shared it between HP_Mini and the VGA capable Macs on the display. THaven't looked for the manual yet, but title looks promising anyway?

https://h10057.www1.hp.com/ecomcat/hpcatalog/specs/provisioner/99/PL766AA.htm

*****Now I've got a 17" lightbox, at least I got rid of the stand and it fits flat on top of other stuff in one of the storage boxen. :

Got my hopes up with the HP LA1751G as it had Custom Scaling, but no option to disable it.  Just choose to maintain aspect ration as it scales. :/

HP L1740 17" and L1940 19" Flat Panel Monitors User Guide

Trash80toHP_Mini said:

HP L1740 17" and L1940 19" Flat Panel Monitors User Guide

Click to expand...

That's just the usual clock, phase, V/H position.  No options for scaling.

On a quick look thru that's what I came up with, but figured you'd want to really go over it.

One thing I'm having a lot of trouble finding is a generic LVDS/TTL LCD controller board, with the usual VGA/DVI/AV/etc inputs, that can do the following:

• Arbitrary resolutions and scan rates for the target LCD, programmable by the user not the seller
  
• Scaling or pixel-doubling
  

If anyone has any leads in such a thing I would be incredibly grateful.

@Bunsen Wow, I didn't think to just look for a generic driver board.  That's a good idea.  Then it wouldn't matter what display I buy.

LOL! I suggested checking for a controller board from the PiVerse yesterday, but I was only thinking about looking on eBay. Checking in with what's been going on in the Raspberry Pi community might be a better idea. @Bunsen that may be a good place widen your search. Who knows, if there isn't a board available, somebody might have figured out how to turn a Pi into one?

Quick check later:

Pi 4 has a Display Serial Interface (DSI) on board and there's a howto for hooking Pi/DSI up to a panel:

https://core-electronics.com.au/tutorials/how-to-use-a-screen-display-with-raspberry-pi.html

Wondering if oddball Mac Video output resolutions/timings might be fed to GPIO, the data massaged on Pi 4 and pushed through the DSI output? Pi might to be able to scale/embed whatever the input resolution/timing in a  might be letterboxed full resolution QXGA (or other) output frame a/o scale it to multiples between input and DSI->LVDS output limitations?
Was looking for info on converting DSI to olde schoole LVDS (if necessary) and came up with:



SN65LVDS302 Programmable 27-Bit Display Serial Interface Receiver
 
WAG here is that Pi4 and a shield or two might become a general purpose converter from any given VGA output to any given panel's LVDS input? Dunno about this stuff, but crazy notions come up and I toss 'em back out, but something along the lines of this might sound like an idea worth researching to somebody?
 
 
 
edit: wondering if ancient LCD outputs from Luggable thru the last non-LVDS PowerBook panel might be handled in the same fashion? [}]





 

Bunsen said:

Arbitrary resolutions and scan rates for the target LCD, programmable by the user not the seller

Click to expand...

I recently bought a super-cheap LCD/Scaler combo that uses a Realtek-based scaler chip that's ridiculously widespread in the cheap boards. I've done digging on the "RovaTool" software mentioned a lot in this guy's posts and I have been wondering if it's worth trying to tweak it, since its out of the box configuration is less than optimal. I don't have the link handy, but there's actually a tool out there that can program the board without a separate programmer if the board has a VGA port wired according to the reference design. (It can pass SPI through the DDC channel.)

That said, these tools are *extremely* user unfriendly, and are mostly for getting the board to work with specific panels. I haven't found anything on how to tweak the input parameters, which is also a thing I'd like to do. It may not be possible with this chip; it seems to be a very TV-centric device.

...Well I finally received the LCD controller for my IAQX10S from China. Doesn't work.

While the backlight lit, nothing displayed on screen, and according to the EDID info the controller is set with a max resolution of 1440x900 (aka typical "we didn't even bother configuring this LCD controller" resolution).

I bought it from this AliExpress seller, best stay away from it.

Awe shoot.