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A friend of mine gave me 2 LCD display driver boards (VGA/HDMI to LVDS). One has RTD2553V chip (from Realtek) and the other has RTD2660H (I cannot share the datasheets because they are not public). The main difference between them is the latter one accepts HDMI input. He said that he's currently using the first one and wants to use the second one due to that difference, so he asked me to check if it is possible without modifying LVDS display connection.

Anyway, I checked the connections between chip and LVDS output socket (2x15 vertical header /w 2.54mm pitch). And I noticed that EVEN and ODD channels are swapped. For example, pin7 is TXE3- in the 1st board but it is TXO3- in the 2nd board. Likewise, pin29 is TXO1+ in the 1st board but it is TXE1+ in the 2nd board. And it is true for all of channel outputs (i.e. if a pin is EVEN on the 1st board, the same pin is ODD on the 2nd board), only VDD and GND connections are matching.

Without further ado, I'm finalizing this verbiage with the actual question. Can it be used? Will that difference cause any problems?

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It should not be used just like the first, I think. For full compatibility, you need to swap EVEN / ODD channels.

And for this you will have to edit the flash firmware on the board.

Display Control Signal Inverted

Datasheet

Try to connect and submit a test image, as you will not be able to "kill" the display in any case.

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  • \$\begingroup\$ Thanks for the answer. Sorry, I've never experienced in LVDS and LCD driving. Correct me if I'm wrong: If I don't want to edit firmware then EVEN outputs of the chip should always match EVEN input of the LCD. So the connections of the cable should be modified. And if I don't want to modify the circuitry/connections then I should edit the firmware so that EVEN and ODD outputs are swapped. Right? \$\endgroup\$ – Rohat Kılıç Jul 5 '17 at 7:53
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    \$\begingroup\$ Yes. Because, if the controller uses two-channel transmission, the conditional "data for pixel N" will be written as "data for pixel N+1". But there is a possibility that the controller is smart enough and can determine the channel swap itself. \$\endgroup\$ – Ruslan Fatkullov Jul 5 '17 at 8:06

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