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I'm have been trying for quite some time now to find a way on how to convert the video signal that comes through the RGB Bus on the TI 84 Plus CE T
to make it possible to connect the Calculator to a TV or use a more "standard" connector.

I'm pretty new to the whole Calculator Modding scene
and I just can't find a way to make it work I was hoping someone of you guys out here
could help me with this problem!

I know what kind of Display is used in the Calc its a:


I'm sorry for my bad english, I'm from Germany.
Welcome to Cemetech, Johniiii

The first thing you're going to have to do is figure out the connector on the module itself. What the connector is called and what the pinout is. The site does say 16bit parallel RGB which could give a few hints as to what you're looking for (probably 5 red bits, 6 green bits, and 5 blue bits all in a row somewhere on the connector) but I don't know of any way to figure that out without an oscilloscope that has bus sniffing capabilities. Generally these are thousands of dollars and can only be found in places like universities or high end makerspaces. There's a great Ben Heck Show about this and definitely countless other videos on youtube covering how to reverse engineer an ldc protocol.

Now, let there be no illusion that this is a simple task. Without a datasheet (and by the looks of it that site was not looking good in that department) for your specific screen, you'll be discovering everything with no help. If you really want to go down this path, please document all of your findings here for all others to use/check/ask questions about, but it's going to be very hard.

Good luck!
Thanks for the nice answer!

I started to dig a bit and found this in the Datasheet Archive:


It seems to fit the Connector and Panel Type.
Well, that certainly is a nice find. If it really is the datasheet for that screen, it basically confirms the RGB565 suspicion. I didn't see any information on actual pinout though. It did have the signals involved for each "system" (the system-80 or 68k) but from what I could see it lacked information pertaining to specific displays, only general protocols. But this is way better than starting from nothing. Nice work
I believe, that it is more like a general Guide on how the Giantplus Displays work and which protocols etc... they use but since Giantplus is actually only making one series of Displays in 3.5 Inch with a resolution of 240x320 with the 16Bit RGB parralel Bus Im quite confident that this gives at least confirmation on the 565 suspicion and makes the whole thing a bit easier.

I sent an email to the Giantplus Techsupportservices and asked if they are willing to give me the exact layout.
Let's see where this goes!
GUYS (and Girls obv.^^) I HAVE VERY GOOD NEWS!!!

I got in Contact with the Manufacturer of the mentioned Display
and I got something very useful back, I cant guarantee that this
Datasheet, or more manual fits every single Display that is used in these
things because TI changes the Displays from time to time, because of cost but
I got the Datasheet for the one that is in mine!

( GiantPlus GPM1421C0 )

This is the Link to the Datasheet!

Have a good one!
This Link: http://www.giantplus.com.tw/en/prod_infos/35-inch-lcd-module-5

is therefore not useful anymore because it describes the wrong Size of Screen!!!

I dont know if GIANTPLUS changed anything on the Pinlayout or on the General Structure of the two Display Sizes!

The one link that is most trustworthy is this one:

Nice find! I'd say grab an oscilloscope and try to verify the pinout listed in that datasheet. If your measurements confirm, then I'd say it's safe to assume the rest of the datasheet is right.
So, I tested the Pins and it seems all good to me, since we have figured this out, how do we or better how do I now convert this Signal that comes to that port to a more standard Signal like HDMI or something like this? Is this even possible? And what do I need to do this?
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