Laurel Electronics LAUREATE SERIES Serial Comunications User Manual
Page 5
Another alternative for RS-485 is to use an RS-232 to RS-485 converter that plugs into the
computer RS-232 receptacle external to the computer and is powered from a +9V DC wall plug-
in adapter. One such unit is the B & B Electronics Model 485OT9L.
-4-
RS - 485 INTERFACE - J3A & J3B
FULL DUPLEX
ISO GROUND
BRX
ARX
ATX
BTX
ISO GROUND
6
5
4
3
2
1
MODEL 485OT9L
TB1
TDB (+) TRANSMIT +
TDA (-) TRANSMIT -
RDA (-) RECEIVE -
RDB (+) RECEIVE +
GND GROUND
RS232 TO 485 CONVERTER
SWITCH SETTINGS FOR MODEL 485OT9L
Baud rate
4800 Baud
-
S1-ON,
S2-OFF
S3-OFF
S4-OFF
9600 Baud
-
S1-0FF,
S2-ON
S3-OFF
S4-OFF
19200 Baud
-
S1-OFF,
S2-OFF
S3-ON
S4-OFF
Echo
-
S5-OFF
2-wire/4-wire -
S6-OFF,
S7-OFF
Termination
-
S8-OFF
Driver Control -
JP1-Jumper on SD
RS - 485 INTERFACE - J3A & J3B
HALF DUPLEX
ISO GROUND
ATX/ARX
BTX/BRX
ISO GROUND
6
5
4
3
2
1
MODEL 485OT9L
TB1
TDA (-) TRANS,RCV -
TDB (+) TRANS,RCV +
GND GROUND
RS232 TO 485 CONVERTER
SWITCH SETTINGS FOR MODEL 485OT9L
Baud rate
4800 Baud
-
S1-ON,
S2-OFF
S3-OFF
S4-OFF
9600 Baud
-
S1-0FF,
S2-ON
S3-OFF
S4-OFF
19200 Baud
-
S1-OFF,
S2-OFF
S3-ON
S4-OFF
Echo
-
S5-ON
2-wire/4-wire
-
S6-ON,
S7-ON
Termination
-
S8-OFF
Driver Control -
JP1-Jumper on SD