node-simplespi

This is a simple and easy to use SPI module for node.js.

I wrote this to have an easy way to control a Adafruit PWM LED driver with my Raspberry Pi ( node-leddriver ), but it should also work with different clients and hosts.

Installation

npm install simplespi

Usage

var simplespi = require( "simplespi" );
 
var response = simplespi.send( "AA00FF", "/dev/spidev0.1" );

The send method accepts a hexcode string as parameter and sends it to the SPI device defined in the optional second parameter. If the second parameter is undefined it uses /dev/spidev0.0.

The value returned is the response of the device in hexcode string form.

Testing on the Pi

First run the following on your Raspberry Pi (with root privileges):

console.log(simplespi.send( "AA00FF" ));

It should return:

000000

Then shortcut the MISO and MOSI pins of your pi and run the same command again. It should then return:

AA00FF

If you got this your SPI device is working.

Enabling SPI on the Pi

If it's still not working, check your /etc/modprobe.d/raspi-blacklist.conf and comment out the entry:

blacklist spi-bcm2708

by changing it to:

#blacklist spi-bcm2708

then reboot your pi and type ls /dev. If spidev0.0 is in the list you're fine and you can repeat the test.