As typical input device, keyboards have special advantages when used for interactions. To give a case for example, passing push-key events to flash via keyboard spares the entire process of going through cumbersome interfaces. Although it's easily for us to come up with the idea of disassembling the keyboard to lead out the keys. But this method has the disadvantage that the key value cannot be changed dynamically. But if only we use a simulation computer keyboard, we can set the push-key time and key value freely. This tutorial, shows how to press a key to trigger an input "HELLO WORLD" into your computer screen via the simulation computer keyboard.
2. Building Process
(1) Follow the below circuit diagram to solder the resistor, USB cable and Dupont line onto the universal board
Note: please refer to the table to find out what each color stands for.
COLOR STAND FOR
After welding, the circuit should be like this:
(2) Connect the Dupont line welded as the upper picture displays to UNO by referring to the table.
UNIVERSAL BOARD UNO
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