David Woolley writes: > If you want fast edges to be reproduced accurately, you must do, as > Unruh says, and terminate the line with its characteristic impedance.
But RS232 drivers won't reliably drive 100 ohm loads. Another possible problem with RS232 on long runs is 60Hz interference due to ground loops. As you suggest, it's best to use 422 for long runs. If you must use RS232 drive the cable with +-15 from a 100 ohm source. It is not necessary to terminate the cable with its characteristic impedance at both ends. -- John Hasler [email protected] Dancing Horse Hill Elmwood, WI USA _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
