LCD Controller Issues

If you are experiencing LCD display issues, most of the issues lie with the LCD cables. They maybe plugged in wrong somehow or be physically damaged.


If you are seeing squares on the LCD:

The usual cause of this is the wrong firmware has been loaded. To be more specific, its likely the wrong board version of the firmware. Unless you upgraded from a MK1 to MK2/S, you likely have a RamboMini 1.3. Make sure when you reflash the firmware, that is the .hex file you are using.

If you are seeing strange/garbled text on the LCD:

The usual cause of this is cables being plugged in incorrectly, so data is still being sent but not being interpreted correctly. Power everything down and double check connections at both ends. Make sure that the shaprie marks correlate with the correct ports.

If you are seeing nothing on the LCD:

It's likely the cables are plugged in incorrectly or are not seated entirely on the pins for the LCD on the electronics. Double check that the cables are plugged in correctly at both ends and they are fully seated. 

Last thing to check is that the LCD cable connectors are making good contact with the ribbon cable. Unplug the entire LCD cable from the electronics and the LCD controller. With just your fingers, press down the black connectors on both ends and apply pressure. Replug and power back up.

If you've tried a combination of suggested things above and still can't get things to work, please contact support at and we'll be glad to help you out.

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