Specifications

October 8, 2003 Networking Alpha Signs (9700-0112C)

52 Appendix

Appendix C—RS485 echo

When RS485 echo is on, data coming into a sign via RS232 is sent back out the sign controller board’s RS485

terminals. This allows information coming into one sign to be forwarded to other signs. The echo travels in one

direction only. In other words, from RS232 to RS485 only.

RS485 echo is best used for modem or wireless applications when the RS232 data source is inside the sign.

However, a typical configuration is as follows:

NOTE: RS485 echo is currently available on the AlphaPremiere 9000 series and aluminum Director signs.

RS232

First sign

Last sign

Middle sign(s)

RS485

RS485 echo ON

RS485 echo OFF

This sign is set up to echo

the incoming RS232 signal

to the other signs via RS485.