Instruction Manual

PTB 200 9 (28)

Digital Barometers

SSD/Operating Manual 24th February 1993 PTB200-O0284-1.1

2.7 Multiple transmitters on one RS 232C bus

It is possible to connect up to 99 PTB 200 barometers to one RS 232C

bus by using a connector box with diodes for each barometer

transmission line and one common barometer receiving line and ground

line (see Figure 6). Each barometer must be initialized to POLL mode

with a specific address (1...99) (see ADDR, SMODE POLL, OPEN and

CLOSE commands). The host computer must have sufficient buffering

to be able to handle several barometers.

GND

BAROMETER 1

BAROMETER 3

HOST

COMPUTER

Fig. 6 Connector box for several barometers on one RS 232C

bus