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Arduino programming: Stacks, classes, and scrolling displays

SCHOOL OF MAKING

Arduino programming:

Stacks, classes,

and scrolling displays

Learn new code skills and impress your friends with the coolest

looking thermometer in the land

I

n our previous Arduino tutorial, we

expanded both our C programming

knowledge and our data visualisation

potential by using a library – we stood

on the metaphorical shoulders of

giants and imported code written by

other developers. Rather than being a cheat

or a lazy option, this is how nearly every project

is developed. Libraries, and their close relation,

the API, allow programmers to utilise all kinds of

advanced functionality without having to constantly

reinvent the wheel. Not only that, but you also

benefit from the programming wisdom that goes

into the development of a library, wisdom that can

sometimes stretch generations when dealing with

old system libraries, more true when programming

with C than many modern languages.

We’re going to use a couple of new libraries in

this tutorial to do some magical stuff that would

otherwise take a year’s worth of tutorials. We’ll

use the same temperature and humidity sensor

from before, but we’re moving on from the hipster

austerity of seven-segment displays to a whole

new world of usefulness – a real bona fide screen.

The screen we’re using is known as an SSD1306.

It’s commonly available and costs very little, and

yet has a bright OLED display with a resolution

of 128 × 64. It’s also tiny, making it perfect for

embedded projects where you need to output a

few more details than a couple of numbers. In fact,

YOU’LL NEED

SSD1306

monochrome

0.96” 128 × 64

OLED graphic

display

DHT11 digital

temperature and

humidity sensor

Right

The completed

project shows both

temperature and

humidity, alongside

a chart for recent

temperature changes

Graham Morrison

@degville

Graham is a veteran
Linux journalist who is
on a life-long quest to
find music in the perfect
arrangement of silicon