Appendix B: Rs-485 Skywan Serial Communication Protocol; Hardware Considerations; Rs-485 Interface On 4 Wires; Transmission Protocol - Advantech SSPBMg–C200–BRE Installation And Operating Manual

12. APPENDIX B: RS-485 SKYWAN SERIAL COMMUNICATION
P ROTOCOL
For rem ote operation, the SSPB is equipped with a monitor and control function. Th
function contains all of the relevant data concerning the control and status signals of th
This is achie ved by usi

12.1 HARDWARE CONSIDERATIONS

In order to use the RS485 serial communication betw n a DB-9 s
25-pin MS connector (J3) of the SSPB, or the 15-p
R S-4 85/RS-23 2 shou ld be used.
1 .2 2

RS-485 INTERFACE ON 4 WIRES

This is a 4-wire full-duplex interface.
In order to maintain synchronization, the RS485 receiver will reset if a message is not completed
within 50 msec of i nitiation.
12.3 TRANSMISSION
Baud Rate
Data Bits
Parity
St op Bits
Minim Response Time
Maximum Response Time
If the SSPB does not respond within the maximum response time, the controller should
cyclically repeat the command.
The SSPB is equipped with a calibrated power sens
antenna from th e r ated outp
th rou gh the M& C RS485 Inte
reported power accuracy is ± 1.0 dB absolute and ± 0.5 dB relative.
ng a fou r-wire RS 485 sign
Follow the wiring described in TAB
PROTOCOL
9600 bp
8
none
1
10 msec
20 msec
ut value to the 20-d
rface for the mo
al.
ee erial connector of a PC and the
in MS connecto r (
s
or for measuring the power delivered to the
B b ac k off. T his
nitoring of the power leve
SSPBMg-C200-BRE
e M&C
e SSPB.
J2) of th e SSPB , a n adap
LE 7 .
value, in dBm, is av able ail
l a nd the ALC The .
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