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Welcome to the project page for the PiXi add-on for the Raspberry Pi. Here you will find all the latest information and all the links that’ll get you up to speed with one of the most unique add-ons you’ll find for the amazing Raspberry Pi!

What is the PiXi?

The PiXi add-on has been designed to expand the I/O capabilities of the Raspberry Pi and provide a low-cost means of introducing the user to the exciting world of digital electronics and FPGA technology while at the same time giving the 'Pi enthusiast' a little more to play with.  You could even use it for prototyping & product development!

It was designed with the intention that it should be a low-cost, fully assembled & tested add-on to a Raspberry Pi that would expand the I/O capabilities a little further and provide a few interesting features of its own. It’s designed to sit directly on top of the Raspberry Pi or you could connect it to the Raspberry Pi using a ribbon cable fitted with two 26-way IDC sockets. It has similar board dimensions to the Pi so that it doesn’t significantly increase the footprint of the Raspberry Pi when it’s mounted on top.

It’ll also fit the Raspberry Pi B+ too. We need to revise the design of the board slightly to better suit both the original Raspberry Pi and the B+ but this is all planned for the next revision.

What can you do with PiXi?

So what can you do with the PiXi. This is quite a hard question to answer because it was specifically designed to be as versatile as possible, within a budget and to include a number of features that would target all sorts of great applications.

Typical Applications of the PiXi add-on:

  • General purpose multi-function I/O expansion for the Raspberry Pi;
  • Promoting electronics in education;
  • School projects;
  • University projects;
  • Experimentation & Fun!;
  • Product development;
  • A low-cost teaching aid providing an introduction to digital logic, FPGAs & VHDL and/or Verilog based logic design and embedded computing.


  • AstroCam – the reason the PiXi board came about… A custom designed astronomical camera using a low-cost CCD and a user configurable readout control system;
  • Audio processing;
  • Race telemetry processor for a racing car;
  • Robotics control;
  • Network or Internet based remote-controlled vehicle;
  • Intelligent low-power remote data logging;
  • Quadcopter controller;
  • Increasing the number of UARTs available on the Raspberry Pi;
  • Increasing the number of SPI channels available on the Raspberry Pi;
  • Logic analyser;
  • Low bandwidth oscilloscope;
  • Weather station;
  • Model train set controller;
  • Software defined radio;
  • Lego Mindstorm NXT controller;
  • Multi-function I2C, SPI, RS232 & RS485 interface analyser & debugger;
  • On-board autonomy for a remote-controlled vehicle… For example, remotely pilot a remote-controlled plane over the Internet via the 3G network, autonomously assisted by GPS / magnetometer based guidance and accelerometer based stabilisation;
  • Development platform for a digital audio analyser, using the expansion interface to get AES-3 or AES-10 (MADI) digital audio into the FPGA for analysis;
  • Motion detection based alarm system for a bicycle;
  • Telescope & observatory controller;
  • Dalek Pi;
  • Custom 8-bit computer;
  • Home automation controller;
  • Need more SPI or I2C interfaces on your Raspberry Pi? Use the FPGA to add more SPI or I2C ports;
  • Custom control panel;
  • Need more than 8 PWM controllers? Implement many more PWM controllers within the FPGA;
  • & there’s plenty more…

A more complete list of example projects can be found here:

Example Projects & Applications:

Where can I find out more?

Full specifications, application notes & other helpful documentation can be found on our downloads page.

Twitter - All of our announcements can be found on Twitter.

Facebook - Our Facebook page also has all of our recent announcements, plus links to pictures and videos that we’ve published.

YouTube - Each time we come up with an interesting application that end up building ourselves, you can probably find a video of it on YouTube

Contact us - If you’d like to get in touch with us about the PiXi add-on for the Raspberry Pi, please feel free to email us at:

If you have an idea for a project that you think could benefit from a PiXi (2.0) then we would love to hear from you with details of your idea or plans. Please email us at with as much detail of the project as you're happy to share with us that we could include on our PiXi Projects page.

We’ve compiled a list of some of the projects and applications that we considered for the PiXi, together with some of the great ideas that have been submitted to us since we first came up with the concept for the PiXi.

Current Status:
(Updated 28th September, 2014)

So where are we with the project… We’re currently working on a couple of last minute examples of what you can do with the PiXi but our primary task for September & October is to get the Kickstarter project compiled and ready for launch. All being well, we will be making an announcement soon so please keep an eye on our Twitter or Facebook pages. We’ll also send out a news email as soon as the Kickstarter project goes live.

Two versions…

We wanted to make the PiXi both highly versatile and low cost so after much deliberation we settled on two basic versions:

The PiXi Model ‘A’, ‘Full’ or ‘Standard’


  • Full specification,
  • 4Mbit non-volatile flash memory;
  • FPGA programmed from the Pi or non-volatile memory for quick configuration
  • 3.3V & 5V digital I/O;
  • 100mA & 2A open-collector I/O;
  • 12-bit 8ch ADC & 4ch DAC;
  • 4 switches, 8 LEDs;
  • Arduino™ Shield socket;
  • RS232 serial I/O;
  • 25MHz Oscillator;
  • On-board 5V switching PSU - accepts 6.5V to 15V external power supply;
  • Intelligent Raspberry Pi power switch;
  • Motion sensor
  • General-purpose platform, ideal for expanding the I/O on the Raspberry Pi, an introduction to FPGAs, prototyping or general use;

PiXi Model ‘A’ Specification (pdf)

The PiXi Model ‘B’, ‘Lite’ version:

  • Reduced specification for lower cost;
  • FPGA programmed from the Pi;
  • 3.3V I/O;
  • 100mA open-collector I/O;
  • 8-bit ADC;
  • 4 switches, 8 LEDs;
  • RS232 serial I/O;
  • 25MHz oscillator;
  • Power from external 5V from the Raspberry Pi;
  • Ideal for expanding the I/O on the Raspberry Pi and for an introduction to FPGAs;

PiXi Model ‘B’ Specification (pdf)

And both versions will probably be available as a kit requiring just the through-hole connectors to be assembled on to the board by the user to reduce the cost even further.