We have been flailing away at rt_com for a couple of days and it still isn't working. Do i have to uninstall the Linux serial driver? I'm using RTL V2.2. As the module was written, with used=0 for both ports, I get a -EBUSY when i run rt_com_setup. I changed the table to make use=1 for both ports and now the module refused to install because the ports are busy. eric