let ptt = SerialPtt::new("/dev/ttyUSB0", PttPin::Rts);
let soundmodem = Soundmodem::new(soundcard.input(), soundcard.output(), ptt);
let app = M17App::new(soundmodem);
let ptt = SerialPtt::new("/dev/ttyUSB0", PttPin::Rts);
let soundmodem = Soundmodem::new(soundcard.input(), soundcard.output(), ptt);
let app = M17App::new(soundmodem);