Same trouble as him, what does a vesa connector look like? I am not quite sure on how to connect it eaither, is all i need to do is wire the appropriate wires into the vesa connector? ty. Gecko
I've asked the original author if i could translate his how-to, he agreed to that. So stay tuned. I'll just be doing the translation of the original how-to. White Modder will do his own how-to.
alright its a Citizen G6486H-FF from a compaq laptop was an old 486 33mhz i have found a datasheet on the net that gives all the details, i can post that and pics if that wud help thnx
datasheet for lcd: http://members.westnet.com.au/silentmusic/g6486h.pdf pics for lcd: http://members.westnet.com.au/silentmusic/front.jpg http://members.westnet.com.au/silentmusic/back.jgp thnx
There are a number of problems you are going to have attempting to utilize the VESA feature connector for this: First you have to understand something about LCD screens. They way they work is as follows: Liquid Crystal is run by things called 'Line Drivers'. These are nothing but chips with a number of addressable switches. You basically tell the chip which switch to turn on or off, which converts this to a voltage on one of the output lines, which then turns a pixel on or off. There are a NUMBER of these chips necessary for any display, this is because you need TWO physical lines for every pixel (power and ground). In addition, LCDs are NOT persistent, meaning, the voltage that is applied only temporarily re-orients the liquid crystal. So all the lines need to be refreshed a number of times a second (in the case of your LCD, 80 hz is the frame frequency, and defines the starting refresh rate). The line drivers are then managed by a thing called an LCD Controller Interface. Depending on the complexity of the interface IC, these can be as complex as an entire system with special serial inputs, CGI (character generator interface), built in RAM controller, etc. Others, are merely nothing but an electrical interface for the line drivers. When ever you send data to a video card, that information is placed into what is called a 'Frame Buffer', and is a chunk of memory which describes the information necessary for the display of each pixel. The frame buffer is read by the controller, and translated to the correct segment ID's/lines for display on the panel. The digital process behind this is quite complex, as things are generally managed a line by a time. A clock interface is used to specify when you are at the top of the screen, when you move from one column to the next, and then when you move from one line to the next. Most LCD panels are refreshed in a R->L manner starting from the Top to the bottom, making the Upper Left Pixel 0,0. The problems you have in interfacing deal with the complexities of the tightly engineered systems: 1. The segment drivers need to utilize a 'bias voltage' to switch the crystals on the display. This needs to match up with the LCD controller interface specs, so as not to destroy the line driver chips or the liquid crystals (by overvoltage). 2. The refresh rates for the line and column sync pulses are generally limited by both the line driver chip types, and the LCD panel (the crystals can only switch so fast). As a result, many are severly limited in which frequencies they will accept, and require some type of conversion otherwise (NOT an easy thing to do). 3. There are generally layered interfaces on most LCD's. Eventhough your graphics card ALREADY has a Frame Buffer, the LCD controller may have another one, requiring the data from one frame buffer to be dumped into the other. This was somewhat alleviated by the introduction of DVI interfaces, however, most LCD controllers still use their own so they can handle situations like 'scaling' the video input to fit the screen and so forth. 4. There is *NO* standard to interfacing to these line drivers. Some have 4 data lines, other require 8 data lines, still others require 32 data lines for input. In addition, just about every LCD controller chip has their own design for how THEY interface to anything, resulting in a LOT of screwing around just to get the inputs/outputs straightened out. 5. Your laptop panel may or may not have a controller built into the panel. More than likely the only chips on the back of that panel are the line drivers, so you will still need an LCD controller interface in front of that. 7. The expensive controller cards you see are expensive, because the board needs to be able to handle many of the different variations of LCD display voltages, frequencies, and line interfaces. That requires an inordinate amount of flexibility, which requires a *lot* of engineering. Most card us the Chips & Technologies CT65535 chip as the main video interface, which a slew of custom designed chips patched into that to allow for the varying voltages and frequencies. Since these cards aren't mass produced, they end up being pricey. 8. Because the laptop mfgs worked directly with the LCD mfgs, they were able to specify how the LCDs worked (what voltages, freqs, etc.) As a result, many of the LCD panels in laptops are CUSTOM designs. A lot of times, there isn't a controller out there in the general market for these displays, because the laptop mfg custom built something in their graphics card instead. You may or may not be able to find a controller which can handle the requirements of the LCD you are looking at. I'm not saying that this is impossible, or a lost cause. It just isn't easy, and *definately* isn't something that can be handled by someone other than an experienced engineer. If the mfgs and LCD panel makers ever took the time to standardize these interfaces, it wouldn't be such a huge engineering exercize. However, there doesn't seem to be enough of a monetary incentive for them to do so, so we are stuck with the 're-design everything from scratch' everytime a new panel comes out.
it is possible, the man of the elec shop (he studied for engineer and so on) said it is possible, but indeed not all screens wil work (incorrect data is on of the many problems) but he thinks that we can put 25% of the screens we have at work [workprogress] (compaq-, toshiba-, ibm-, dell- screens are ready to be tested. we are collecting the data from all the screens we have (will take at least 2 weeks) and we are collecting some videocards (some old, some new so we can see if it works on all videocards.[workprogress]
Okay, you listed the LAPTOP mfgs, but who are the *panel* mfgs. AO Optronics? Samsung? Hitachi? These are the *real* limiters, as both DELL/COMPAQ/TOSHIBA commonly switch mfgs even during a single product run, depending on price/availability at the time. I'm sure everyone would be more interested in the panel mfg/model rather than the laptop mfg/model.
true but like i said we are opening the screens and are searching for the datasheets and so on, get it? (sorry for my bad english)
I've got some in my machines, one is S3 Virge and the other is an S3 Trident. I got them for $4 a pop from a friend of mine, I'd reccomend you just look for a PCI video card, and ask for a picture of it, if you see a double row of pines near the top left of the card (assuming you are looking it with the PCI connector being down and the backplane being left) and that's a VESA connector. I will try and post a pic later tonight.
Are we talking about using the method in the Dutch thread, or some other way of that results in (nearer) full functionality?
few pics here, do they have vesa 1. http://i19.ebayimg.com/03/i/01/58/d4/93_1_b.JPG http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=2788205014&category=27388#ebayphotohosting 2. http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=2788832491&category=27388 3. http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=2787935814&category=27388
Has anyone actually checked out low settings on their display? It's easy to forget just how poor a picture 16/256 colours makes for. I get the impression at least a few of us think that we're going to get a second display with a great picture using this method Not to say it isn't a very interesting project for those who've already got the panel sitting around doing nothing and just need the gfx card. I'll certainly be keeping an eye on what comes out of this thread
