Understanding the RTD2660

Sponge

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Hi,

I'm playing around with a RTD2660 based driver board (PCB800851) and small display that came with the driver. The pair seem to work well out of the box using the HDMI input. There is an AV pin, however connecting to it doesn't work (camera, PAL, rasp PI analogue output).

I've tried to trace the track from the AV pin to the RT2660 but can't be sure which pin it is headed for.

so, I have a few questions

1) Which input to the RTD2660 is the analogue video input? I'd have guessed it would be an ADC pin such as 51 to 54, but these all look like they are attached to a flash memory chip on my board..

2) I've had a read about the Rovatool and I have a i2C/USB debug device on order as I want to delve deeper into the RTD2660 for future projects. If I am able to extract firmware from the RTD2660, will I be able to change a few things and flash it back? I'm hoping to be able to do things like disable HDMI, or remove the text when there is no input etc.

3) How hard is lashing up display firmware from scratch if you know some of the display specs from datasheets?

4) There a lot of stuff on github that I'm digesting. Does anyone have some guidance for the best place to start from?

5) I'm probably going to be messing with many displays, but the TTL connectors seems to be rather varied (and LVDS too). Are there any standard configurations that have been adopted for these connectors and display pin configurations? I'm looking to have as versatile driver board as i can to cover as many displays as I can. Ideally I'd use something like the pcb800099 but the thought of having to translate pins from one fine pitch connector to another is daunting if every display has a different requirement.

6) I2c interface, other than flashing firmware, is there anything this is used for on the fly, or is this dependant on the MCU code in the RTD2660? Could I control brightness and overlay over i2c if I code the MCU firmware?

7) If there is anything more on the RTD2660 than a afternoon of googling can't find, I'd love to know about it.

thanks for any help.
 
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I likely know less than you about the topic, but wanted to make sure you've seen this build where someone made their own custom PCB that has a RTD2660 on it:

(finished) Swiitch 2.5 - BocuD's third Wii Portable - Post #34
https://www.bitbuilt.net/forums/ind...uds-third-wii-portable.2749/page-2#post-44690

If I'm reading the schematic in "LCD.pdf" attached to that post correctly, on that board the RTD2660's pins 45/46 are used for composite video input. There are no guarantees the same pins are used on your board/firmware (or that your board's firmware accepts PAL input?), and I don't have a PCB800851 to check. I enjoy taking things apart and figuring out how they work, but trying to mix and match displays/controllers/firmware sounds like a painful ordeal to me. Good luck.
 

Sponge

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Hi Leftbrainstrain, I hadn't seen that build, so thanks for pointing it out. I have found another diagram of much worse quality that used pins 47/48 for the same purpose, so I agree with you and it looks like its any pair of those pins 41 to 48 as long as the firmware matches up.

I really need to tweak the display boards RTD2662 firmware, I got my project working, but it wasn't a clean solution. I know the chip can do better if only I could steer it :)
 
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