User manual

Connect Tech Xtreme/104-Plus, PCI-104 and PCI/104 Express Family User Manual
Revision 0.08
22
Line Bias/Termination
The RS-422/485 transceivers, both transmit and receive are optionally biased and terminated to
produce a stable idle condition through jumper selectable resistors.
Jumper Block and Mode Settings for 12 Port Opto
The following jumper block diagram depicts typical settings on a four-port selectable
Xtreme/PCI-104 12 Port Opto. Each port has two banks of jumper blocks, Jx.1y and Jx.2y.
Where ‘x’ is the port number and ‘y’ is the jumper number of that power.
Important Note!! We recommend that jumper removal and installation only be performed when
the power to the Xtreme/104 card is off.
Figure 11: Examples of Various Jumper Block Settings for the 12 Port Opto model
J1.1A
J1.1B
J1.1C
J1.1D
J1.1E
J1.1F
Mode Bit 0
Mode Bit 1
Mode Bit 3
Multidrop Enable
RXD B&T
RXD B&T
J1.2A
J1.2B
J2.1A
J2.1B
J2.1C
J2.1D
J2.1E
J2.1F
Mode Bit 0
Mode Bit 1
Mode Bit 3
Multidrop Enable
RXD B&T
RXD B&T
TXD/RXD B&T
TXD/RXD B&T
TXD/RXD B&T
TXD/RXD B&T
J2.2A
J2.2B
J3.1A
J3.1B
J3.1C
J3.1D
J3.1E
J3.1F
Mode Bit 0
Mode Bit 1
Mode Bit 3
Multidrop Enable
RXD B&T
RXD B&T
TXD/RXD B&T
TXD/RXD B&T
J3.2A
J3.2B
J4.1A
J4.1B
J4.1C
J4.1D
J4.1E
J4.1F
Mode Bit 0
Mode Bit 1
Mode Bit 3
Multidrop Enable
RXD B&T
RXD B&T
TXD/RXD B&T
TXD/RXD B&T
J4.2A
J4.2B
J5.1A
J5.1B
J5.1C
J5.1D
J5.1E
J5.1F
J6.1A
J6.1B
J6.1C
J6.1D
J6.1E
J6.1F
Mode Bit 0
Mode Bit 1
Mode Bit 3
Multidrop Enable
RXD B&T
RXD B&T
Mode Bit 0
Mode Bit 1
Mode Bit 3
Multidrop Enable
RXD B&T
RXD B&T
TXD/RXD B&T
TXD/RXD B&T
TXD/RXD B&T
TXD/RXD B&T
J5.2A
J5.2B
J6.2A
J6.2B
RS232 RS485 Full
Duplex 4-wire
RS485
2-Wire
RS485 Multidrop
4-wire
Low Power
Shutdown
Loopback
Bias and Termination Resistors
The (B&T) Bias and Termination resistors are use in RS485 communications. All other modes
these jumpers should be removed.
The B&T resistors are selected using jumpers Jx.1E/Jx.1F and Jx.2A/Jx.2B.
RXD and TXD/RXD Termination/Bias: Install this pair of jumpers to enable a 150 ohm
terminator across the RxD+ and RxD- or TxD+ and TxD- pins for the corresponding port. A
biasing network is also enabled that drives the receiver to an inactive or safe mode. The receiver
can still receive data from another device and the biasing helps to prevent the reception of data
generated by noise on the transmission line. The two jumpers for the termination/bias must be
installed and removed as a pair.
Bias and Termination Notes:
For 2-wire and 4-wire multidrop wiring networks the B&T resistors are only installed
when the Xtreme/PCI-104 12 Port Opto is the first or last device in the wiring network.