Intresting project on my mind!

[fLYtRap]

Hi All

I have a desktop computer that doesn't have a monitor. So far I have been viewing it on my TV, but I made some changes in my place and where I have computer now I don't have a TV set.
My project is to hook up a laptop screen to that desktop 8)
I am looking for some diagrams or advices on how to do it.
I have a 15.0" laptop screen that I pulled out of an old Compaq Presario 1800 laptop. This unit has a 20 pin video connector and a separate inverter hooked on 2 pin connector. Is there any way that I can put those together. I realize that I will have to came up with my own wires and how the hell am going to hook this all up?

[redwudz]

Well, maybe. The problem is that some of the necessary driver circuitry for the display is likely on the motherboard, integrated with a whole lot of other circuitry with most laptops. If you can find where the video signal goes into the laptops video driver circuits, you might be able to input your signal there.

It would be fairly complex to input it to the display itself. You would have to know a whole lot more about the display. If you had a laptop that was somewhat modular and followed how a desktop PC is set up, there may be some surface wiring that goes to the video module that you can intercept, but it's a long shot.

Not to discourage you, but it won't be easy.

I would start by digging around on the Compaq's website. And do some searching of the internet for information about that laptop. Some manufacturers have fairly complete information about their computers available online. There are also a few sites that have saved that type of info. Good luck.

[fLYtRap]

I have a video card in my desktop that have S-Video out (standard RCA Jack), so I thought maybe I could use that. I know its not an easy task, but I am stubborn and I want to do it

[redwudz]

S-Video is not likely to do it. Maybe VGA if you can locate the input or output on the laptop MB.

I admit, I've had the same thought myself. I have a older 12" laptop that works perfectly well, but only with W95. It would be nice to use the display for a more modern computer or for a utility display. But knowing how integrated and compacted laptops are, I really don't want to get into it.

If you can find the video circuitry on the laptop's motherboard, you are halfway there. The display part of a laptop (The screen) is unlikely to have much in the way of circuitry in it. It's probably on the motherboard. The laptops' video 'card' would feed to the power driver circuitry for the display and then to the display itself. You may only be able to intercept it at the input or output of the video 'card' to be able to get any output to the LCD display.

Dig around on the internet a little. With all those 'case modders' out there, someone may have done similar to what you are thinking. I picked up a old PS-ONE display a year ago (5" screen) that has composite input. The modders use them on their PCs for a 'window' and graphics display. It works great for a small color monitor. I got it off E-bay for $15US.

[edDV]

Follow the wires in the old laptop to the LCD controller chips (controller and scaler) then use Google to find the reference design and application notes.

Like this one for a stand alone LCD monitor (VGA and DVI in). Many laptop graphics chips integrate LCD control and scaling into the graphics chip and thus drive the LCD panel directly.

http://www.freescale.com/files/shared/doc/selector_guide/SG2058.pdf

[fLYtRap]

o man...

[edDV]

All that is in very few chips. Freescale is the spun out Motorola semiconductor division.

To compare, here is a reference design for a LCD-TV from Texas Instruments. Much more is going on in a TV. Even so, it reduces to a few processing chips, a circuit board and a micro controller.

http://focus.ti.com/docs/solution/folders/print/327.html