I'm trying to put a 9 pin d-sub serial connection on a pc without one. Where do I connect it? I have usb 1 and usb 2 headers and 1 1394 header. Am I able to connect to any of these?
No. The headers look similar but they are NOT compatible. The easiest thing to do would be to get a USB-to-serial dongle adapter, but that entails the OS/drivers being aware that there is a USB-to-serial adapter and looking for the attached device on a USB port instead of a COM or tty port. The best solution would be to get a PCI or PCI Express add-in serial port card, which does show up as a "native" serial port to the OS, programs, and drivers. However, that eats up an expansion slot in your computer and these can be more expensive than a USB serial adapter.