A fully working RepRap Discount Smart Controller for your Melzi printer.
All functions work including the SD card.
If you have a Melzi board on your printer you might want to try this PCB.
It uses a modified pins.h file from the Marlin software to allow the port to work.
Please don't hesitate to comment on this and suggest upgrades.
You will need to create a PCB from the Eagle cad files attached.
Change out the pins.h file from the Marlin software.
Hook up your controller as shown and all should be working.