Vaisala PTB220 - Manual (Page 15)

C HAPTER 3___________________________________________________________ G ETTING STARTED
V AISALA __________________________________________________________________________ 9
CHAPTER 3
GETTING STARTED
As the PTB220 series digital barometers always have an RS 232C
serial interface, the user is requested to use this interface when
operating the barometer for the first time. The RS 232C is the most
useful and reliable interface for commissioning the barometers with
various software settings.
The RS 232C serial interface of the PTB220 barometers does not
provide handshaking lines (such as DSR, CTS or DTR). If the host
system requires handshaking lines, appropriate external connections
have to be made in order to enable the communication with a PTB220.
See Appendix on page 81 for more details on how to connect the
handshaking lines.
NOTE 1. The sending of PTB220 is controlled with XON/XOFF (software
handshaking)
2. The buffer of the barometer can be cleared with .
The RS 232C serial interface and power supply pin assignment is as
follows:
1 2 3 4 5
6 7 8 9
F IGURE 3-1 9-pin female subD-connector
PIN SIGNAL
2 TX
3 RX
5 ground for the RS 232C
7 ground for supply voltage
9 supply voltage (10...30 VDC)
F IGURE 3-2 RS 232C and power supply pins