We have a ton of TRENDnet adapters we purchased for the PC side. Those adapters usually require a driver though, and we haven't been able to find out which ones might be compatible. From my understanding, they do run some flavor of Linux so it's entirely possible that would work. We haven't tried putting a USB RS232 adapter on the TV yet. I'm also glad to see you mention a USB-RS232 adapter.there is an option in the Service Menu that says 'USB Serial'. Glad to know I'm not the only one who has run into this issue.
