The "not all" part is where some of these devices use the hardware lines to handshake. CTS/RTS lines are used and have to be supported for most devices. However, some devices use the DSR and DTR lines to augment the basic handshaking. I think that it is these lines that the USB cables don't support.
You also have to have a correct cable, although most null modem cables that you buy support 90% of the devices. I have come across devices where I had to have a "breakout" box and make my own cable. On 11/22/06, Darcy Brodie <[EMAIL PROTECTED]> wrote:
Sorry - hit the wrong key I work in the security industry. Almost all of the electronic security (alarm systems, card access systems, closed circuit camera systems, most telephone systems for programing / backup / restore functions) all require a serial connection. We have tried the USB => Serial adaptors, and they will work for some of the security products, but not all. Darcy Darcy Brodie wrote: > And I disagree with not making them. I know of a lot of applications > that still require serial connections > > Darcy > > > Mitchell Brown wrote: > >> I'm pretty sure someone makes a PCMCIA card for this purpose. Try >> memxit.com <http://memxit.com> >> >> I agree with the decision to no longer make them though - I mean, who >> uses them?! >> >> On 11/22/06, *Kin Wong* <[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>> >> wrote: >> >> As you know, new laptops are being made without serial ports. Does >> anyone know or has had success with serial ports cards or usb serial >> cables for laptops? >> >> > > > _______________________________________________ > clug-talk mailing list > [email protected] > http://clug.ca/mailman/listinfo/clug-talk_clug.ca > Mailing List Guidelines (http://clug.ca/ml_guidelines.php) > **Please remove these lines when replying > > > > _______________________________________________ clug-talk mailing list [email protected] http://clug.ca/mailman/listinfo/clug-talk_clug.ca Mailing List Guidelines (http://clug.ca/ml_guidelines.php) **Please remove these lines when replying
_______________________________________________ clug-talk mailing list [email protected] http://clug.ca/mailman/listinfo/clug-talk_clug.ca Mailing List Guidelines (http://clug.ca/ml_guidelines.php) **Please remove these lines when replying

