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Quick Start with Processing

Mon, 03/31/2008 - 19:01 — artbus

This looks like a lot of stuff

because every little step is spelled out

Processing is the easiest program to get working with ArtBus, and anything that makes Processing work is relevant to other programs as well.  So that's where we'll start. There are advanced choices for some of the setup items, but those aren't covered here.

Set up your computer and Processing

  1. If you've installed the Arduino system, you can probably skip this section.
  2. Downlad and install Processing for your platform.
  3. Go to FTDI's website and get the usb-to-seral port driver for your computer. Drivers are available for Windows and Mac. The one for Linux comes installed.  Do the install, then REBOOT. (sometimes more than once on Mac...?)

 

Set up and check your ArtBus Boards

  1. Download the Processing configuration tool for ArtBus. It's name is ArtBus_term.pde.  Unzip the folder and put it in your Processing sketches folder. Don't open the sketch yet. Just get it in there ready to go.
  2. Plug the ArtBus FTDI USB-to-serial adapter and at least one ArtBus board into your computer. The blue LED should come on indicating that power is on, and the green LED should blink three times showing that the ArtBus board has just been reset.
  3. Open the  ArtBus_trem.pde sketch and start it.
  4. Push the reset button on an ArtBus board. The green LED should blink three times, and you should see a greeting in the window. If you see a greeting in the ArtBus_term window, basic setup is done. This also means that your ArtBus devices are at serial port number 0 (zero). If you get a blinking red light that means you pushed the setup button by mistake. Just push the reset button and it will be ok.

If nothing happens in the ArtBus_term window, or if you get red error messages in Processing's terminal window, then the FTDI driver isn't talking properly to Processing. This could be because

  • things aren't plugged in, or
  • the FTDI driver isn't insatlled right, or
  • the serial port Processing is trying to use isn't the one that has the FTDI adapter connected to it.

When you start ArtBus_term.pde with everything connected, a list of serial ports appears at the bottom of the Processing editor. On Mac they should include one that looks like "/dev/tty.usbserial-FTQVBIO0". On Linux it should look like "/dev/ttyUSB0", on Windows like "COM9". Processing wants to know which one on the list to use and for that number to be put in the [ ] in the line below:

port = new Serial(this, Serial.list()[0], 115200); //Choose serial port from list

Serial.list()[0] means the first serial port in the list, and [0] works almost all the time. Other values could [1] or [2], etc.

When pressing the reset button gives you a greeting, the hardware and computer setup is finished. If you get a blinking red light that means you pushed the setup button by mistake. Just push the reset button and it will be ok. Don't close ArtBus_term.pde yet -- there's one more thing...

Find the address of your boards

Since the ArtBus_term program is happy now, it's time to ask each of your boards what its name is, so that you can talk to it from Processing. If the ArtBus_term.pde sketch isn't still open, open it.

One at a time, press the reset button on each board and read the greeting message in the ArtBus_term window. The address of a board is given in the first few words of the message: "Hi from A..." The address of this board is A. It also tells you what kind of board it is, (analog or digital). The address is always an upper-case letter. Make note of the addresses. You'll use these in your program.

Finish up the computer setup

Close the ArtBus_term.pde sketch. Processing allows multiple sketch windows to be open at the same time, but only one program can own the serial port.

 Connecting to the boards

Basic connections for analog and digital input are shown on the Analog and Digital Input Diagrams page. The analog input section shows how pots and photocells connect. A word of CAUTION: the center lead on the pots in the diagrams are yellow -- be sure the center lead on the pot goes into the correct hole! 

Basic connections for digital output are shown on the Digital Output Diagrams page. Please remember that hooking anything other than small electronic signals to the outputs will require extra components!