Quatech DS-200, User Manual

Page: 34 / 41

7.7 Termination Resistors
Optional line termination resistors are provided for the input signals of
each of the DS-200/300’s RS-422/485 ports. The user has the option of
selecting RS-422 termination (
100Ω
), RS-485 termination (120
Ω
), or no
termination. Line termination may be selected or removed using jumper
block J1. The board is shipped with no termination selected.
8-16
120
Ω
7-15
100
Ω
Serial 1 AUXIN
6-14
120
Ω
5-13
100
Ω
Serial 1 RXD
4-12
120
Ω
3-11
100
Ω
Serial 0 AUXIN
2-10
120
Ω
1-9
100
Ω
Serial 0 RXD
PINS
JUMPERED
ON J1
TERM SIZE CHANNEL SIGNAL
Figure 24 --- RS-422/485 Line Termination
J1
1
2
3 4 5
6
7
8
10
11 13
14 15 16 12 9
Figure 25 --- Line Termination Option Block
7.8 RS-422/485 Peripheral Connection
The DS-200/300 connects to peripheral equipment through two female
D-9 connectors. The serial port connector definitions are listed in Figure
28.
7-6 Quatech Inc.