Rs485-1 Line Reception, Rs485-2 Line Repetition; Rs485 Tx/Rx Line; Serial Terminations/Connections - Videotec ULISSE PLUS Manuel D'instructions

7.4.5.3 RS485-1 line reception, RS485-2 line
repetition
With this type of setting it is possible to connect more
than one device in cascade. The signal is repeated
from every unit, making it possible to markedly
increase total distance.
Control
RS485-1 RS485-2
Keyboard
Max 1200m
Fig. 41
j It only works with mono-directional
protocols.

7.4.5.4 RS485 TX/RX line

With this type of setting it is possible to obtain a
bi-directional, half/duplex, communication on the
RS485-1 line.
The RS485-2 serial line is not used.
Control
keyboard
Fig. 42
j This function is only available for
bi-directional protocols (e.g. PELCO,
AMERICAN DYNAMICS, Macro, etc.).
RS485-1
Max 1200m
RS485-1
TX/RX
Max 1200m

7.4.6 Serial terminations/connections

The diagram shows two dip-switches that are used to
configure termination of the serial line.
Every peripheral that is situated at the end of a line
must be terminated using the appropriate dip-switch
in order to prevent signal reflection and distortion.
dip-switches 1 and 2 terminate serial lines RS485-1
and RS485-2 respectively.
Unlike the previous cases in this table when
j
the dip-switch rocker is up it represents the
value 0 (OFF) while if the rocker is down it
represents the value 1 (ON).
TERMINATION OF RS485 LINES
Description DIP 2 DIP 1
Line RS485-1
Line RS485-2 ON
OFF
Tab. 11
Configuration
- ON Terminated
- OFF Not terminated
- Terminated
- Not terminated
23