What to do with spare Pismo LCDs

[Dennis Nedry]

I needed new clutch hinges for my Pismo so I won an auction on eBay that contained two sketchy LCDs and one set of hinges. So I have a couple of spare Pismo LCDs. One is supposed to be dim and the other supposedly doesn't work at all, but I have spotted a crack in the ribbon cable, so that may be the only problem.

I would very much enjoy to frankenstein something up with these. Does anyone have the spec on the connector and/or how complicated it would be to convert to something standard? The ribbon appears to have 14 conductors that hook up to the LCD's 20-pin port. There are some others that divert over to the microphone connector on the ribbon.

 

[coius]

http://www.applefritter.com/holygrail

Excerpted from the Applefritter FAQ
Q: How do I turn this laptop/iMac screen into a monitor?

A: Put simply you don't. Whilst it is possible to use a laptop (or iMac) screen as a monitor it takes a large cash investment and a good understanding of electronics. If you are lacking in either of these departments don't bother, buy a cheap LCD with VGA connection on eBay instead.

If you really want to know more about using a laptop display on another computer then do a search of the hacks sections with 'holy-grail' as your keyword. You can also try visiting Earth LCD for more info regarding the required convertor boards.

The LCDs in iMacs fall under the "laptop screen" category as Apple designed the iMac's onboard video circuitry to drive the LCD directly, like laptops do. There's no intermediate controller to which you can simply feed a VGA or DVI signal.

Here's one of the best explanations of why using a laptop LCD for a monitor is a difficult project I've seen so far, courtesy of Eudimorphodon:

Laptop displays simply don't speak the same language as CRT monitors, electrically speaking. It requires a complex wad of electronics to turn output meant for a CRT into input suitable for an LCD, and that wad of electronics is referred to as the 'controller'. You won't find a controller you can salvage in your laptop anywhere, because it 'speaks LCD' directly, and thus doesn't need one.

It's not just a matter of pasting wires together, which is what everyone wants to think. Those controllers sell for anywhere from $150 to $300, and for most installations require custom cables and power supplies which may well run you another $150.

 

[Unknown_K]

Some people have basically recased a laptops guts in a box and made the LCD seperate using a home made cable. There are old ISA cards that talk directly but they are probably for older screens.

While turning a VGA output into something a LCD can use is difficult (without buying the expensive board to do it), I would think a DVI out to LCD would be simpler (keeping everything digital).

 

[~Coxy]

Addenum to Holy Grail with a bit more info, from http://theducks.livejournal.com/492985.html

I hang out on a number of modding boards around the internet. The "Holy Grail" is people posting and expecting an easy answer about re-using the LCD out of their old laptop (see http://www.applefritter.com/holygrail ). The response is generally "blah blah needs a custom controllers blah blah too hard blah blah". To an extent, it's right. You do need a controller, and it's not that easy. But it's not as hard as they tend to make it out to be. There are two main types of signalling - TTL and LVDS. Newer stuff (last 8 years or so) is all LVDS. LVDS comes in four flavours - 8 bit 2 channel, 8 bit 1 channel, 6 bit 2 channel and 6 bit 1 channel. The more bits/channels, the more data can be thrown at the LCD. Then the hard part is getting a cable. If you check the right datasheets, you may find that panels/controllers can be swapped around pretty easily.

The products: http://www.aitendo.co.jp/product/395 (LVDS and TTL) and http://www.aitendo.co.jp/product/797 (LVDS and TTL - no DVI/Sound) - with these two products (maybe a few adaptors too), and a bit of time and skills, you could almost certainly get any LCD shipped in a laptop or desktop in the last 10 years working. But look at the price, and the fact you'd need to ship them in from Japan. Is it /really/ worth it? I don't think so.

I'm personally waiting for 20 and 24 inch iMacs to start becoming obselete (mm 2012 maybe? ) and see who is first to market with a kit to turn them into regular LCDs. Extra kudos for keeping the iSight working.