I have done some device development and will be glad to offer my "two cents" on why COM ports still continue to be used even though USB is "newer-better".
First, USB is made simple for the user by being complex hardware. A fully compatible COM port driven device requires only a couple of easy to get parts and can be made for under $5.00. You can do it even cheaper if you don't want to actually meet the RS-232 spec. On the other hand the simplest approach to USB (that I know of) is an ASIC board that costs about $40 in prototype quantities. It is essentially a full PIC microcomputer dedicated to the USB task. Next is the software. Handling I/O through the COM port is easy in MS Windows and Linux (and KDE). Lots of free or cheap drivers are available to just drop into your application. The last time I tried to do a USB driver, the entry fee was several hundred dollars or LOTS of time writing the thing. As to computerless communications, you can implement COM to COM communications with some very simple PIC hardware. Trying to build a USB host with its associated software is a huge job. Finally, USB to COM port expansion boxes are reasonably priced so adding more ports is now a plug and play exercise. If software will recognize lots of COM options, I will be happy with it. Since the ham market is pretty small (albeit devoted), I think this would be a good balance of capability with cost and effort. Just my opinion, 73 Ron, AG5RS
