Summary

I have an original, very old Wanhao Duplicator i3. From the first pre-order old. I have been working on updating the software, by installing a newer version of Marlin (thanks, Nitrogen777 ((https://www.thingiverse.com/thing:2450111))). In the process, I toasted my display, via electric shock, and the only drop in replacement was $45 from some specialty website. No thanks, The RepRapDiscount Full Graphics Smart Controller is surprisingly similar, and runs for about $10.

After poking around, trying some other guides, I eventually just tested the pins, and found someplace on the back of the original board that they went, found the similar place on the new board, and wrote down what pin that was. Eventually, I mapped all 10 wanhao pins to pins on the 20 EXP1/2 connectors.

Attached is a PDF with the corresponding pins. Here is a description of the titles:

• Pin Name: The name in the RepRap schematic that this pin is for
• Wanhao Name: The name printed on the (not exactly a) melzi board. See the grainy picture I took.
• Wanhao Pin: The pin number on the melzi/wanhao board. If you're unsure of which pin is pin 1, 2, 10, etc, look at the Wanhao Names compared to the connector in the picture.
• EXP1 Pin: The pin on the EXP1 connector of the RepRap Display
• EXP2 Pin: The pin on the EXP2 connector of the RepRap Display

I'm very sure the RepRap SD card won't work. I'm also sure that this isn't the same pinout as the standard melzi board. If you are trying to flash Marlin, then the pins_.h file can be found in the thing above by Nitrogen777. If you still have the original wanhao firmware, then this should work out of the box.

As I mentioned, I have the very oldest version of this printer. If you have a v1.1 or a plus, or v2 or whatever, there's a good chance this will be different. Let me know if this was useful.