In this lab, you’ll build an alternative computer mouse using an Arduino Leonardo using pushbuttons to move the mouse left, right, up and down. You’ll see the difference between reading a digital input continually and reading for a change of state.
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For this lab you will need the following parts:
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NOTE: The sketches contained in this lab will cause the Arduino Leonardo to take control of your mouse. Make sure they’re working properly before you add the mouse commands. The example doesn’t introduce the mouse commands until the end of the lab. Instead, messages are printed to the serial monitor to tell you what should happen. When you’ve run this and seen the serial messages occurring when you think they should, then you can add the mouse commands safely.
The sketches here will work on an Uno until you add the mouse commands. So you can test this on an Uno simply by commenting out any line that says Mouse.begin() or Mouse.move().
Prepare the breadboard
Connect power and ground on the breadboard to power and ground from the microcontroller. On the Arduino module, use the 5V and any of the ground connections:
Attach a pushbutton to digital pin 2. Connect one side of the pushbutton to 5 volts, and the other side of the pushbutton to a 10-kilohm resistor. Connect the other end of the resistor to ground. Connect the junction where the pushbutton and the resistor meet to digital pin 2. (For more on this digital input circuit,see the Digital Input Lab)
Add four more pushbttons
Repeat the last step, connecting four more pushbuttons to pins 3 through 6.
Follow the same steps as you did in the first Mouse Control lab to read when the pushbutton on pin 2 is pressed. Your code should only print out a message when the button changes state. Similarly, set up a global variable to track whether or not you’re controlling the mouse, called mouseIsActive. Each time the pushbutton on pin 2 is pressed, change the state of this variable from false to true, just like you did in the first mouse control lab.
For more detail: Mouse Control With Pushbuttons