Lantronix 900-422 Benutzerhandbuch

Seite von 116
Chapter 3: Installation and Hardware 
 XPress DR+ User Guide 
22 
 
Note:
 Termination resistors (R = 120 Ohm) are used to match impedance of a 
node to the impedance of the transmission (TX) line. Termination resistors 
should be placed only at the extreme ends of the data line, and no more than two 
terminations should be placed in any single segment of an RS-485 network. The 
termination resistors may not be needed for your application.  
Figure 3-5. Termination Resistor for 2-Wire Connection 
 
9-Pin RS-232 to Serial RJ45 Cable (P/N 500-103)  
The included Lantronix (P/N 500-103) RJ45-DB9F serial cable assumes you are 
connecting a typical PC Com port to the XPress DR+ serial port. This cable is pinned to 
provide full serial line control to an RS232 DTE device. Lantronix offers a 
comprehensive list of cables and adapters to simplify device connectivity to the XPress 
DR+. See 
Appendix B: Lantronix Cables and Adapters
 for a full listing.
 
Figure 3-6. Lantronix P/N 500-103 RJ45-DB9F Serial Cable Pinout 
8  CTS (In) 
1 RTS (Out) 
1  DCD (In) 
2 DTR (Out) 
6 DSR 
(In) 
3 TXD 
2  RXD (In) 
4 Signal Ground 
5  Signal Ground
5 Signal Ground 
3 TXD 
(Out) 
6 RXD 
4  DTR (Out) 
7 DSR (In  ) 
7  RTS (Out) 
8 CTS (In) 
  DTE, 9-Pin 
 
 
 
XPress DR+ 
    Female 
 
 
 
Serial RJ45