When connects to full-duplex or
half-duplex, in order to prevent the
reflection or interference of signal. You
need to connect electric resistance at the
end of line(120
Ω
1/4W).
V
、
The connection diagram of communication
USB/RS-422 transfer
1. RS-422 point to point 4 lines full-duplex
communication
2. RS-422 point to multi-points 4 lines
full-duplex
3. between BF-850 full-duplex
USB/RS-485 transfer
1. RS-485 point to point 2 lines half-duplex
2. RS-485 point to multi-points/2 lines
full-duplex
3. between BF-850 half-duplex
VI
、
breakdown and elimination
1. the failure of data transfer
A. check the USB line connects right or not
B. check RS-422/RS-485 line connects
right or not.
C. Check the terminal connects well or not.
2. data loss or mistake
A. check the transfer speed and format
same or not of both two sides.
T/R+
T/R-
RXD+
RXD-
1
2
3
4
BF-850
R+
R-
T+
T-
RS-422 Equipment
PC1 = >
USB
T/R+
T/R-
RXD+
RXD-
BF-850
R+
R-
T+
T-
RS-422 E
equipment
PC1 = >
USB
R+
R-
T+
T-
R+
R-
T+
T-
1
2
3
4
RS-422 E
equipment
RS-422 E
equipment
PC1 = >
USB
T/R+
T/R-
RXD+
RXD-
1
2
3
4
BF-850
A
< = PC2
USB
RXD+
RXD-
T/R+
T/R-
BF-850
B
3
4
1
2
PC1 = >
USB
T/R+
T/R-
RXD+
RXD-
1
2
485+
485-
BF-850
RS-485 E
equipment
485+
485-
RS-485 E
equipment
1
T/R+
T/R-
RXD+
RXD-
2
BF-850
PC1 = >
USB
485+
485-
485+
485-
RS-485 E
equipment
RS-485 E
equipment
PC1 = >
USB
A
T/R+
T/R-
RXD+
RXD-
1
2
BF-850
< = PC2
USB
B
T/R+
T/R-
RXD+
RXD-
1
2
BF-850
