RS-422 & RS-485 are more your industrial standards, bringing capability of interfacing multiple devices and having longer cable runs (eg 1 km) through the use of balanced pairs for Tx and Rx. The original RS-232 standard that defined a variety of pin functions (but not the use of DB-25 connectors - that's an ISO standard), used +/- 12 V for data and specified that no damage was to occur up to 30 V (?) is not what you typically see implemented these days with 3-wire, TTL logic (or even 3.3 V logic) in devices like Palms & Zauri. Despite the changes, "RS-232" continues to work for simple tasks like interfacing to microcontrollers.
Kevin. On Wed, 2007-11-28 at 00:09 +1100, Voytek Eymont wrote: > so how do you control say some industrial device (if not through a serial > port)? > > whilst perhaps they're somewhat past on a pc, I think they're still > 'current interface' on things like industrial things, no ? > > (one reason why I'm glad I still have my old Palm 3C with serial i/f) > > > > -- > Voytek > -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
