Working node.js SPI code connecting a Raspberry PI with a PIC32MX

var SPI = require('spi');

var spi = new SPI.Spi('/dev/spidev0.0', {
    'mode': SPI.MODE['MODE_1'],   // clock idle low, clock phase active to idle.
    'chipSelect': SPI.CS['none'], // 'none', 'high' - defaults to low
    'maxSpeed': 8000000
  }, function(s){s.open();});

var rxbuf = new Buffer([ 0x00 ]);

var state = 0;

function writeToSpi(){
    var txbuf = new Buffer([ state ]);
    spi.transfer(txbuf, rxbuf, function(device, buf) {
        console.log("Wrote " + state + " to SPI");
        console.log("Received " + buf[0] + " from slave");
    });

    state++;
    setTimeout(writeToSpi, 100);
}

writeToSpi();