I get this kind of "silent" behavior when the serial port settings are not correct. Make sure you have the baud rate matched, etc. You might need something like this for your URI line in /etc/cups/printers.conf: DeviceURI serial:/dev/ttyS0?baud=19200+size=8+parity=none+flow=soft Good luck! =S.Coffin GV Computing scoffin at comcast.net