LCD is a blank screen need help

So I’m messing around a bit with the Rambo and the LCD and finally got power to it the lights turn on and everything but there’s nothing coming up on the screen. Can anyone explain to me what all this firmware stuff is because I thought that the board came ready to go if you bought it through V1.

There are 4 ways to plug in the LCD, two will be black, one will be blue, one works. If they are in the correct port, turn them around.

The plugs sometimes get installed backwards, so you can just shave off the tab with an exacto knife. Or some folks just pull the socket off the board, the pins will slide out the bottom, and spin it 180 and push it back on.


So how will I know when I have it right?

When you see text! It can’t hurt anything to swap the connectors around. Just power it off between tries.


This is an area where there are so many photos on the forums that it’s not clear quite what to do, it took me quite a while yesterday to figure out the correct method, but the answer was in the documentation. Basically you have plugged it to the board upside down.

Here’s the photo from the documentation - note “RED STRIPE ON THE LEFT FOR LCD CABLES” On the screen side,(face down) the plugs face down, I’ll take the cover off my screen in a minute or two and photograph it.

got it! awesome thanks!

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This works for me! :wink: - I’ve posted this for the benefit of the next person to have the problem.


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I hope that is helpful.

In the past, the red stripe is based on whatever side if the bed the person making the cable slept on that morning.


But as long as the red stripe is on the left on both parts - given that the plugs are now not captive, that shouldn’t matter. Or am I missing something (again)? :flushed:


4 options, try them all. Really there are only 2 if you make sure port 1 is going to port 1 and they are facing the same way. If that is wrong, point them the other way on the Rambo. Reboot and boom, picture.

This is why I have the shields taken off the Rambo’s custom. There are two LCD standards. The only way to have them both is not be specific to the ones I sell.

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No, that’s a good point. I hadn’t thought of that.

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Unless the guy building the display or board put the sockets on backwards. It happens sometimes. It’s a good starting point though.

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