Issues with firmware / LCD screen



I purchased all the electronics from the website. I have the Mini Rambo and the LCD. I have everything connected now. Nothing on my screen is popping up. I can see the little green LEDs on the board and the LCD making a little noise so I know I have power to it. I tried redoing the firmware but my computer wasn’t able to connect to the mini rambo…?


I downloaded the Arduino 1.8.9 and the repetier to control it. Nothing seems to be connecting. What am I doing wrong??

If you got it from the website then it’s already flashed. If the lcd is showing nothing then the lcd wires are probably reversed. Sometimes the wires are keyed wrong. I’m not sure if the ones Ryan sells are or not. Any way you plug it in wrong (of the 4 ways) it won’t hurt it, but it only works one way.

Another common problem is using the USB, but not connecting the 12V power. In that case, the LCD will be completely off.

Jeff, I have switched around the wires multiple times and nothing happened. I have the power and the USB plugged in at the same time. Any other suggestions?

A picture of your wiring would help.

Have you tried flipping the actual plugs? as in take the plug and flip it 180 and plug it in, that what Jeffe means when he says they are sometimes keyed wrong. you can pull off the plastic part from the lcd if it has one.

I gave this a try last night and that did it. I put them on like it was pictured on the assembly page but after flipping them 180 on the board it worked perfectly! I got it moving! Thanks

High five!