cat value 

With a button pressed, you should see a 1. When the button is not pressed

you should see a 0. Using the up arrow, you can recall previously run

commands.

C++ Examples

We’re assuming that you’re using the Eclipse IDE as detailed in our Beyond

Arduino tutorial. If you aren’t, you’ll need to go to that tutorial to get up to

speed.

Hardware Connection

Hardware support for this library is simple; one basic red LED and one

momentary pushbutton. We’re using a 2N3904 NPN transistor to drive the

LED, however, as the drive strength of the outputs on the Pi Block is quite

weak. As you can see in the diagram, you’ll also need a couple of 1kΩ

resistors and a single 330Ω resistor.

While we’ve used GPIO45 and GPIO46 in this example, this code can be

used with any of the pins on the Pi breakout. The GPIO to MRAA pin map

can be found in the Resources and Going Further section.

Code

Follow the instructions in the programming tutorial to create a new project

named “SparkFun_Pi_Block_Example”. Once you’ve created the project,

open the “SparkFun_Pi_Block_Example.cpp” file and replace all the

existing code with the code block below.

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