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1. 4 push-buttons
2. SERIAL connector
3. Connector Box
5. Soldering iron and accessories
As you can put the buttons wherever you want, I decided to put mine in one old diskbox.
I decided to use a network cable to connect the Serial connector to the buttons, because its easier to organize and makes the work simplier and faster.
Step 1: Step 1
1. Looking in the scheme, we see that we have to connect one side of each buttons to one cable, these will be solded in the pin number 4.