Tarantula board upgrade

[Bill_L]

I have 2 Tarantulas. The 1st came with with a Mks base V1.4.
The 2nd came with a Mks Base V1.2

The Lcds won’t work when switched with other board.

I bought a Mks Gen L2.1 for the 1st TT.

The 1st Lcd won’t work with it, but the 2nd Lcd will.
I bought a Mks Gen l v1 before (before I had the 2nd TT) and and the Lcd didn’t work with it so I returned it.

Both Lcds look identical (except for the exps connector positioning), and have the same numbers on them.

I can’t find anything that would explain the differences.

Help!!!

Bill

[mykepredko]

I just did some research - Pin 10 of EXP 2 is D31" on the MKS Base 1.2 and it’s "N/C on MKS Base 1.3 and later but I don’t think that would make a difference.

Looking at the backside of the boards, I wonder if the connector keys are reversed - what happens when you keep the LCDs with the controllers that work and just swap the cables?

[Bill_L]

I tried every combination of switching them even end for end.
No luck.
I’ve looked for jumpers on all boards… Hoping to find something.
I have Some electronics background. But this is BeYond me!!!

[Jason]

I think this is the one you have to put the connectors in backward from the way they are keyed.

Does that backlight come on for the screen? that’s the tell for needing to reverse the connector.

[Bill_L]

WWOOOOOWW

Thank You!!!

I just plugged it in backwards and it Works

The other day I noticed the the key way and block on the board . . . . . . . But didn’t think to compare them!!!
Or to flip the plugs!!!

The funny thing is the 1 on the right has the connectors backwards and is the 1 that works with
the Mks base v1.2 and Mks Gen L v2.1

[Jason]

perfect, glad that worked, Love the funny things that come across when upgrading.

[Bill_L]

It’s just So Wrong that the plugs are installed wrong… and then work only with certain boards.
Then the right orientation doesn’t work!?!?!?