port8 = cpu.getIOUnit(IOPort.class, "P8");
port8.addPortListener(this);
IOUnit usart0 = cpu.getIOUnit("USCI B0");
if (usart0 instanceof USARTSource) {
radio = new CC2420(cpu);
radio.setCCAPort(port8, CC2420_CCA);
radio.setFIFOPPort(port8, CC2420_FIFOP);
radio.setFIFOPort(port8, CC2420_FIFO);
((USARTSource) usart0).addUSARTListener(this);