Introduction

Computer interface

When we think in a interface, probably is something that you can interact with the computer screen, keyboard or/and mouse.

Step by step, new interfaces are ready to use. Sensitive, olor, touch, or combination of anyone. Let's work with the classic interfaces: screen and buttons.

Summary

Input and interface

Show a LED blinking, blink at the same time a screen green window, push a button and change the blinking frequency in both.

Content (linked):

Assignment:
Blink red and green

Blink a red LED and a green window

Two IDEs

Arduino and Processing

First step is to program a board (used in week 6) with arduino.

I wish that a led blink slowly and when a push a button, blink faster. Finally, send via seria a "n" if the button is "not pushed" and send a "p" if the button is pushed.

Easy script.

At Processing, I wish that open a window and change the background color depens on the character coming from serial port. Change to green background color when the red led is blinking.

Finally, de effect is:
- Green window and Red LED blink at the same time
- The blinking frequency depen on the button.

Let's work!

Arduino code

Description:
First I included software serial in order to communicate via serial port. Then, define mySerial as Serial and activate input and desactivate output. Defined LED and Button pins and inicialize button state as "off".
Start using serial at 9600 rate and defining ledpin as output and buttonpin as input.

Inside the void loop I code a infinite loop, reading the button. If button is on then blink fast the LED and send a "p" throught serial port. If button is off (not pressed) then blink slowly the LED and send a "n" via serial port.

Processing code

Description:
First import processing serial library. Open a window 640x360, define myPort as the serial port used.

Capture string value from serial port, if value is "n" then change color. That will produce a blink everytime blink the LED on the board.

Download here both scripts

Description:

Processing and Arduino working at the same time

In this video you can see how it works on the PC screen processing software. The PCB is connected via serial port (FTDI) to the Lap Top.

You can see the ISP connected too, while it was been programming the microcontroller.