int clockRate = 1000000; Device[] devices = FTDIInterface.getDevices(); if (devices.length == 0) { // Error handling } Device dev = devices[0]; Spi spi = new Spi(dev, clockRate, SpiMode.M0, false); spi.open(); // Write a single byte to the SPI bus byte[] result = spi.transactReadWrite(new byte[] { (byte) 0xA5 }); spi.close();