![background image](http://html.mh-extra.com/html/advantech/bb-vesp211-series/bb-vesp211-series_user-manual_2858006013.webp)
BB-VESP211x Serial Servers
:
13
CHAPTER 3. INITIAL SETUP AND CONNECTIONS
This Chapter describes how to setup and connect BB-VESP211x Serial Servers.
Note: In this section devices to be connected to the serial server’s serial connection are referred to as the “serial device”.
CONNECTING THE POW ER SUPPLY
Connect a
DC power supply
by plugging a 12 VDC power source into the barrel jack on the top of the
serial server. The center connection must be positive (+). Polarity of the connection is indicated on the
label on the front of the serial server.
Note: A 12V DC power supply is included with each serial server.
Note: The power supply must be capable of supplying 2.5 Watts maximum.
CONNECTING BB-VESP211X SERIAL SERVERS TO SERIAL DEVICES
BB-VESP211x Serial Servers can be connected to serial devices using RS-232, RS-422, RS-485 2-wire
and RS-485 4-wire.
RS-232
The
RS-232 interface
supports seven RS-232 signal lines (TD, RD, DTR, DSR, RTS, CTS, DCD) plus
Signal Ground.
Signals are single ended and referenced to Ground. Default communications parameters are 9600, 8, N,
1 and no flow control implemented.
Note: The serial server is configured as a DTE. If it is connected to a serial device configured as a DTE, use a null
modem (cross-over) cable. If the serial device is a DCE, use a straight-through cable.
RS-422
The
RS-422 interface
supports two signal pairs: TDA (-), TDB (+), RDA (-), RDB (+) and GND. The data
lines are differential pairs (A & B) in which the B line is positive relative to the A line in the idle (mark)
state. Ground provides a common mode reference.