Hello all!
Like many of you, I've been wondering what to do with a beloved iMac G4. Where I work, we're retiring several 20" models, and most of them have been perfectly operational.
Two of them, however, are not. One seems to boot up, but has no video and the other partially boots, but never completes from DVD or from the internal hard drive. My wife and I have both got functional models, but I've wanted to take the one that has an operational LCD and adapt it to a Mac Mini I have.
I've been researching the information for a bit now, and using the information found near the bottom here (
http://www.applefritter.com/node/18351) it looks like many of the TMDS cable wires have been identified. There is, however, a lack of three of the wires being known for sure, and two open ports.
TMDS is the signalling protocol for DVI, so based on the DVI TMDS protocol spec (
http://www.ddwg.org/lib/dvi_10.pdf), a single link DVI channel requires only the 0, 1 and 2 data channels and associated shield pins, and the TMDS clock. This accounts for most of the pins. 1-4 (Vcc and GND) and 17-21 are still unknown assuredly.
Looking up the specs of the closest SilImage DVI processor chip, a PanelLink receiver chip that seems to corroborate (as well as i can tell; still picking this all up) the ideas about a DDC link as well.
(
http://www.siliconimage.com/docs/SiI-DS-0023.pdf)
So, I've removed the LCD panel from my dead 20" and found that it runs an IDTech 20 WSXGA+ IPS panel, model M201Z2
And located the tech specs for it (
http://www.gblcd.com/datacenter/idtech/M201Z2-M01.pdf) (found open on Google) Which list the specific pinouts for the TMDS in cable to the 30 pin flat connector on the back of the LCD panel.
Three channel TMDS with shields, DDC 3.3/5v power, a DDC channel. Yep, looks like it should be DVI compatible.
Now, tomorrow or over the weekend I'll be tracing out the TMDS -> 30pin wire and ensuring that the referenced connector pinout is right and then try adapting it to a standard DVI. That and working on getting the pinout for the Apple inverter board, which is bolted to the backside of the back chassis of the LCD housing and is connected to the joiner wire that joins the inverter, microphone, power indicator LED, fan and speaker connectors.
I'll have pictures as well, but it does look a little bit more attainable than a laptop LVDS display.