Processing 2.1 + Oracle Java + Raspberry Pi + Serial + Arduino = ☺

Hey! This is very old and there’s an officially supported version out now coming out very soon.

Update for Raspberry Pi 2/Processing 2.2.1/Processing 3.0.5: Raspbian now ships with Java 8, and Processing only likes Java 7. oracle-java7-jdk is still in the repos, so install that, and follow the instructions below. It’s a bit flakey, but when it runs, runs quite fast on the Raspberry Pi 2. You might have more luck running Processing.js or p5.js in the browser.

With Sun Oracle hardfloat Java now available, Processing now runs at a decent clip on the Raspberry Pi. My old instructions are now very obsolete. Here are current, tested instructions for installing it under Raspbian.

[This is a particular solution to installing a Serial/Firmata-enabled Processing 2.1 distribution on a Raspberry Pi. Processing still has issues with other aspects of visual programming (particularly video) that I’m not addressing here.]

A lot of software is installed here, and much of it depends on previous steps. Don’t jump in mid-way and expect it to work.

Update the system

Always a good plan if you’re doing major upgrades:

sudo apt-get update
sudo apt-get dist-upgrade

Install Sun Oracle Java

sudo apt-get install oracle-java7-jdk

Check if the right version is installed as default: java -version should give

java version "1.7.0_40"
Java(TM) SE Runtime Environment (build 1.7.0_40-b43)
Java HotSpot(TM) Client VM (build 24.0-b56, mixed mode)

If you get anything else, you need to make Sun Oracle’s version the default:

sudo update-alternatives --config java

Download & Install Processing

Go to Download \ and get the Linux 32-bit version.  It’s big; about 100 MB. I’m going to install it in my home directory, so the base path will be ~/processing-2.1. Extract it:

tar xvzf processing-2.1-linux32.tgz

Now you have to remove the included x86 Java runtime, and replace it with the Raspberry Pi’s armhf one:

rm -rf ~/processing-2.1/java 
ln -s /usr/lib/jvm/jdk-7-oracle-armhf ~/processing-2.1/java

You should now have a Processing installation that will run, but there’s some more we need to get serial and Arduino support.

Install the  java Simple Serial connector

Download and extract it:


Now overwrite the jssc.jar that ships with Processing with the one you just downloaded:

mv jSSC-2.6.0-Release/jssc.jar ~/processing-2.1/modes/java/libraries/serial/library/

(You can remove the jSSC folder now: rm -r jSSC-2.6.0-Release)

Test Processing’s serial support

You’re almost there! Fire up Processing:


and try Perhaps the World’s Most Boring Processing Sketch:

// Example by Tom Igoe

import processing.serial.*;

// The serial port
Serial myPort;

// List all the available serial ports

Screenshot from 2014-01-07 20:08:32When this runs (it’s a little slow), you should get a single line of output, which should start /dev/tty___:


(I have an Arduino Leonardo attached, which usually appears as an ACM device.)

Installing Arduino/Firmata support

(I’m not going to go into uploading Firmata onto your Arduino here. All I can recommend is that you use the newest version at firmata/arduino, rather than the old code bundled with your Arduino distribution.)

Exit Processing, and download from firmata/processing. Extract it into your Processing sketchbook:

unzip -d ~/sketchbook/libraries/

For tedious reasons, you also have to rename one of the files:

mv  ~/sketchbook/libraries/arduino/library/Arduino.jar  ~/sketchbook/libraries/arduino/library/arduino.jar

Start up Processing again, and  save Most Probably the World’s Second Least Interesting Processing Program™:

import processing.serial.*;
import cc.arduino.*;
Arduino arduino;
int ledPin = 13;

void setup()
  arduino = new Arduino(this, Arduino.list()[0], 57600);
  arduino.pinMode(ledPin, Arduino.OUTPUT);

void draw()
  arduino.digitalWrite(ledPin, Arduino.HIGH);
  arduino.digitalWrite(ledPin, Arduino.LOW);

Screenshot from 2014-01-07 21:13:54
What this sketch does is emulate the µC’s “Hello World” program, Blink. It flashes the board’s LED once per second. Boring? Yes. But if it worked, you have a working Processing 2.1 installation on your Raspberry Pi. Go forth and make more interesting things.
(Props to bitcraftlab/wolfing for the basic outline for installing Processing, and for samaygoenka for the prodding needed to update and test the Processing installation process. If you’re still stuck, the Processing 2.0 Forum and the Raspberry Pi Forum are good places to ask.)


Here are the complete 1988-vintage Sun manuals “Using NROFF and TROFF” and “Formatting Documents” scanned just for you. I’d scanned these in 2000, and they’d sat on a forgotten archive volume since then.

Update: there are better versions on the Internet Archive: Using NROFF and TROFF and Formatting Documents, all as part of the Sun Microsystems, Inc. manual collection.

(if you need to get your troff on, go to Ralph’s

archival, snarkival

We live in a Scarborough neighbourhood, so that means that people use the side door. Front door’s for people who know no better. So we need a Side Door sign to guide the unschooled.

On the left is one I just printed. The one on the right — same printer (HP Photosmart C5180), same paper — has been taped to the glass on our front-facing screen door since December 2007, in full sunlight. It’s barely legible. (And yes, it has slightly different fonts/layout; the original was done on a PC in OpenOffice, the replacement in LibreOffice on a Mac.)

So whenever an inkjet crows about “Archival Inks!”, remember: four years to fade to white. Do you need your images to last longer?

who loves the sun?

After my solar course, I’ve been messing about with the UO SRML: Sun chart program. It shows sun angles and day lengths throughout the year.

Toronto: where I live

Glasgow: where I'm from. Not much sun there, but looong summer days

Phoenix, AZ is pretty sunny

I think I'd freak out if I lived at the equator: every day is nearly the same length!

Mombasa, Kenya: point your modules north!

Not much sun in far north Alert; sometimes, the sun doesn't set — sometimes it doesn't rise

I don't think I'd mind living in Glasgow — Glasgow, Guyana, that is.