5
6
KEY:
^ S1-1, S1-2, and S1-4: only one switch can be ON at any time. The
other two must be off. It is recommended that you, the user
disconnect (the model 2086 Series) while changing configurations.
* JP4A: If this jumper is off, only the RS-485 transmitter is controll-
ed by RTS or DTR. If this jumper is ON, both the RS-485 transmit-
ter and receiver are controlled by RST or DTR. When the transmit-
ter is off, the receiver will be ON, and similarly, when the transmit
ter is ON, the receiver is off.
** JP3A & JP3B: Both jumpers or either On or off. When the jumpers
are ON, the RS-485 transmitter and receiver are connected direct-
ly together. This will only function in HDX. When the jumpers are
off, the RS-485 transmitter and receiver are disconnected from
each other. This can be operated in either HDX or FDX, depend-
ing on the setting of JP4A.
Switch S1: RTS Control
When Switch S1 is in the On position, the DTE input signal RTS (Pin 4) is
used to control the transmitter of the Model 2086 Series. In this mode, when
RTS is high, the 2086 Series transmits data from the RS-232 port to the RS-
485 port. Switch S2 and S4 must be OFF position when Switch S1 is ON.
S1
Setting
On
RTS Controls the Transmitter
Off
RTS Control is OFF
Switch S2: DTR Control
When Switch S2 is in the ON position, the DTE input signal DTR (Pin 20)
is used to control the transmitter of the Model 2086 Series. In this mode, when
DTR is high, the 2086 Series transmits data from the RS-232 port to the RS-
485 port. Switches S1 and S4 must be OFF position when Switch S2 is
ON.
S2
Setting
On
DTR Controls the Transmitter
Off
DTR Control is OFF
Switch S3: Reserved
Switch S3 is reserved for future use and must remain in the OFF position.
Switch S4: Transmitter Control
When Switch S4 is in the OFF position, the input of RTS or DTR controls
whether the unit can send data (based on the configuration of switch S1 and
S2). In this setting, and when in the appropriate signal is high, the 2086 Series
can transmit data from the RS-232 port to the RS-485 port. When S4 is ON,
the 2086 Series transmitter is always enabled.
S4
Setting
On
Constant Transmitter
Off
Transmitter is controlled by RTS or DTR
3.2 JUMPER CONFIGURATION
Jumper straps JP3 and JP4 are used to control two-wire/four-wire,
half-duplex/full-duplex operation,and receive impedance, respectively.
*NOTE: Default Settings shown in bold italics
INTERFACE CARD STRAP SUMMARY TABLE
Strap
Function
ON
Off
JP3A
2 Wire/4 Wire Mode
2 Wire
4 Wire*
JP3B
2 Wire/4 Wire Mode
2 Wire
4 Wire*
JP4A
Half/Duplex
Half Duplex
Full Duplex*
JP4B
Impedance
120 Ohm
12K Ohm *
Transmission
S1-1^
S1-2^
S1-3
S1-4^
JP4A* JP4B JP3A & JP3B**
Mode
RTS Control DTR Control Reserved always off RS485 TX always ON
RS-485, FDX,
Transmitter is
always on
off
off
off
ON
off
n/a
off
RS-485, FDX,
Transmitter is
controlled by
RTS
ON
off
off
off
off
n/a
off
RS-485, FDX,
Transmitter is
controlled by
DTR
off
ON
off
off
off
n/a
off
HDX, 4-Wire
controlled by
RTS
ON
off
off
off
ON
n/a
off
HDX, 2-Wire
controlled by
RTS
ON
off
off
off
ON
n/a
ON
HDX, 4-Wire
controlled by
DTR
off
ON
off
off
ON
n/a
off
HDX, 2-Wire
controlled by
DTR
off
ON
off
off
ON
n/a
ON
SWITCH COMBINATION CHART
