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iMac G4 TMDS to HDMI

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iMac G4 TMDS to HDMI: Final

Hello everyone.

Some days ago, I got intrigued to find out about iMac G4 mods. I have read DremelJunkie's blog. The thing is that he uses DVI. I wanted HDMI, but I didn't find anything on Internet. I made a pinout based on DremelJunkie's guide, but I use HDMI instead, after some research on HDMI signal and DVI adaptor pinouts:
Pinout.png
View attachment Pinout.pdf

Guard3
 
Last edited:
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Hey. I searched for these DVI-D and HDMI pinouts, and I believe I am correct. I used DremelJunkie's guide and an iMac G5 TMDS cable pinout to HDMI. I believe the chart I made is accurate, but I just haven't tested it...

Thanks for the reply! I've seen your post, and you're amazing!

Guard3
 
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Hey. I searched for these DVI-D and HDMI pinouts, and I believe I am correct. I used DremelJunkie's guide and an iMac G5 TMDS cable pinout to HDMI. I believe the chart I made is accurate, but I just haven't tested it...

Thanks for the reply! I've seen your post, and you're amazing!

Guard3
hello! help me please!

I'm doing the connections and do not have much experience and can tell me if I made the right connections?



Red 1 and 3
Blue 7:09
Green 4:06
white 2,5,8,11
orange 16
Black: 19
brown 10
violet 13
gray 17


leftover pink, red / black, light green, light blue and orange / brown I do not know where to turn.


am I right?
 
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Ok... I think you confuse me there...
 
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How's this going– are you soldering the tiny cables to an HDMI cable? Tricky work! I was thinking about this myself for my (first ever) mod, considered using an old HDMI cable, which had been stripped to allow access to the cables, rather than working on the tiny contacts.

Would that be the best way to go about things. Any suggestions most welcome.

redmere-3b-2.jpg
 
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hello i wanna back to factory pinouts with my imac g4 17 inch culd you plese give me scheme original inverter pinouts :crazy: i have 2 sockets 21 pin and 16 pin i need to know which one colour of wire put to proper hole in socket help !
 
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CONECTOR HDMI MEXICO copia.jpg



It likes me More and Looks easier than make the DVI connector.

So as the diagram said. Red is on the VEDID port (pin 18 HDMI) that has 3.3V

and Yellow, Purple and Orange would have 3.3Volts, So, Can I join that pins to the VEDID with the red cable?


And what about the 17 pin of HDMI? it says to GROUND. Do I need to Grey, Blue and Green?

Sorry for my newbieness
Thanks


I Posted a Diagram based on the table that you posted here and Stripping an HDMI cable and following the wires on HDMI with a Multimeter/Continuity Test. And I found that colors.

Note that the connector is looking to the front.


But now I have more doubts.
  • If theres no wires in some pines, for example for weld the Shield wires from the iMac. Can I weld all Shield cables together on 17 PIN HDMI.?


  • I understand that Blue, grey and green from iMac will be to the 17 pin HDMI.


  • The table said RED wire from iMac,plugged to 18 PIN HDMI is it right? I know that this pin provides 5VCC.
Its not a problem? I doesn't plugged a kind of Resistor??

  • And what about yellow, purple and orange from iMac, it says that will be plugged to 3.3V, Would be plugged to PIN 18 HDMI Through a resistor?
  • PIN 19 (HOT PLUG) and pin 18 HDMI (5v) are linked through a 1kOhm resistor?
 
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Hello everyone.

Some days ago, I got intrigued to find out about iMac G4 mods. I have read DremelJunkie's blog. The thing is that he uses DVI. I wanted HDMI, but I didn't find anything on Internet. I made a pinout based on DremelJunkie's guide, but I use HDMI instead, after some research on HDMI signal and DVI adaptor pinouts:
View attachment 125650
View attachment 125573

Guard3
I probed as you say.


I have a 17" inch iMac G4, welding cables identifying it. I use a stripped HDMI connector rescued from an HDMI cable. and a Parallel cable(It has a lot of color cables inside it).

the Hotplug pin are welded with SDA though a 2kOhm resistor.

So, when I plug the HDMI cable to my computer. I only can see a white screen with a lot of lines, vertical and horizontal lines, like scrambled video.

What Am I doing wrong?.

Thanks.
 
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I know this is a bit of an old feed, but will this work to convert the tmds port on the imac motherboard to hdmi (out) or is this about getting the old imac display to accept an hdmi signal because i need both,

Im taking out the g4 part of the imac to turn the case into a hackintosh and i want to salvage the g4 part just for the fun of it. I have gotten the g4 part to start to do the boot chime but i can't see anything without the display. i'm trying to connect the g4 motherboard tmds port to the hdmi on the back of my TV.
 
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