
Connect Tech Xtreme/104-Express User Manual
Half Duplex Mode
In this mode the TxD+/- line driver is enabled only when data is transmitted and RxD+/- is disabled when data is being transmitted. This mode is typically used in either point-to-point 2- wire connections OR in multi-drop 2-wire bus connections. This mode requires software setup in Control Panel – System – Hardware – Device Manager – Ports – CTI Xtreme/104 PCI Express UART Serial
Port.
Multi-drop Mode
In this mode the TxD+/- line driver is enabled only when data is transmitted and RxD+/- is enabled all the time. This mode is typically used in multi-drop 4-wire connections. This mode requires software setup in Control Panel – System Properties – Hardware – Device Manager – Ports – CTI Xtreme/104 PCI Express UART Serial Port.
Line Bias/Termination
The RS-422/485 transceivers can be configured to terminate and produce a line level mark condition on the receiver, and/or terminate the transmitter. These options are enabled through on-board jumper selectable resistors. These options are typically used in multi-drop 4-wire or half duplex 2-wire connections.
Jumper Block Settings
The following jumper block diagram depicts typical settings on an interface-selectable Xtreme/104-Express. (See Figure 1 for location of jumper blocks.)
Figure 2: Jumper Block Diagrams
Jumper Block Summary
RS-485 Selection
TXD Control
RXD Control
RXD +/- Termination/Bias
RXD +/- Termination/Bias
TXD +/- Termination
RS-232 | RS-485 | RS-485 | RS-485 |
| | | | Full Duplex | Half Duplex | Multi-Drop Slave |
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NOTE: You must configure your jumper block settings before installing the Xtreme/104-Express into your system.