= yaml = title: Raspberry Pi author: ashankar@ sort: 3 toc: true = yaml =

Vanadium can be used to write software for RaspberryPis. This page details how to set things up so you can build and run Vanadium Go binaries on them.

Prerequisites

You need a RaspberryPi with an installed operating system. See installation instructions at raspberrypi.org. Advanced or adventurous users may want to install Raspian directly.

Building on a RaspberryPi

You could use the RaspberryPi as your complete development environment - write code, compile it and run it all on the Pi. To do that you will:

1. Need the Go compiler. Unfortunately, there are no official Go compiler distributions for the processor architecture of the Pis. You could compile it from source, but might prefer Dave Cheney's unofficial distribution.
2. Download the Vanadium sources:

   export GOPATH=$HOME/vanadium  # Or any other directory of your choosing
   go get v.io/x/ref/...
   

At this point, you should be ready to develop your own Vanadium binaries and build them using go build or go install.

Cross-compiling from your laptop/desktop

Developing and building on the Pi is all great, but if you have a laptop/desktop that you prefer to use instead - which has all your editor customizations, screen size, keyboard you love etc., then you can also build binaries for the RaspberryPi on it. The catch is that your laptop/desktop must be running Linux.

Once Go 1.5 is released and we remove a few vestigal C code, these instructions should become much less onerous. Furthermore, you will be able to build binaries for your Pi running Linux on your laptop/desktop running either Linux or Mac OS X, courtesy significant improvements in the Go compiler's support for cross-compilation.

Till then:

1. Install the jiri tool as per the contribution guidelines.
2. Setup the cross-compiler using jiri v23-profile install arm

Let‘s say you’re building a binary (such as the principal command-line tool) for the machine you‘re developing on, you’d likely do something like:

jiri go install v.io/x/ref/cmd/principal

To build it for the Pi, use:

JIRI_PROFILE=arm jiri go install v.io/x/ref/cmd/principal

This will place the binary under $JIRI_ROOT/release/go/bin/linux_arm/principal. You can then copy this binary using scp or some other mechanism to your Pi.

Using the GPIO ports

Your RaspberryPi projects might involve some circuit manipulation using the available GPIO ports. Search the web to settle on which of a variety of Go libraries to manipulate the GPIO ports you'd like to play with.