NodeJS loopback example for troubleshooting SPI communication on Raspberry Pi GPIO

spi_loopback.js

var rpio = require('rpio');

var rxBuffer = rpio.spiTransfer(new Buffer('HELLOSPI'), 8);

for (var i = 0; i <= 7; i++) {    
	process.stdout.write(String.fromCharCode(rxBuffer[i]) + (i == 7 ? '\n' : ' '));
};