Campbell Scientific PWS100 Present Weather Sensor - Manual (Page 33)

Section 6. Installation
The location of the dip switches on the board is shown in Figure 6-9 and the
dip switches themselves are shown in detail in Figure 6-10. The following
settings are available:
PWS100 dip switch settings:-
0 = off; 1 = on.
switch 1 slew rate
0 slow slew rate (default)
1 fast slew rate
switch 2 communication mode
0 RS232 (default)
1 RS485 (note – load resistor may be required – see Section 6.3.6.1)
switch 3 duplex mode
0 full duplex (default)
1 half duplex (RS485 – see Section 6.3.6.1 below)
switch 4-6 serial communication baud rate
switch
654 Baud
Rate
000 300
001 1200
010 9600
011 19200
100 38400
101 57600
110 76800
111 115200
(default)
switch 7 reserved for future use (default off)
switch 8 load factory defaults at power up
0
normal operation (default)
1 load factory defaults
6.3.6.1 RS-485 Half-duplex mode
In half duplex mode, the transition from transmits (Tx) to receive (Rx) modes
and vice versa are subject to the following timing rules which may need to be
considered when interfacing other devices:
• The sensor waits for a gap of 1 byte period plus 10 ms without receiving
data before switching from Rx to Tx and echoing/responding.
• Sensor has a 1 millisecond Tx to Rx turn around time.
6-11