Dewetron DEWE-ORION-0824-20 Series, Technical Reference Manual

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DE-M080801E • DEWE-ORION-0824-20x • Technical Reference Manual • Printing version 1.1.2 • March 19, 2014
DEWE-ORION-0824-20x
2.8 RS-485 interface
The DEWE-ORION-0824-20x is suited with an RS-485 interfaced as standard. The baud-rate is fixed to
9600, 8 Data, 1 Stop bit and no parity. This interface is used for configuration of the DAQ and MDAQ signal
conditioning modules. Also the acquiring of PAD and EPAD from DEWETRON is possible with this RS-485
port. The interface of the main board and the expansion boards (DEWE-ORION-0824-202 with counter ex-
pansion) is controlled separately.
2.9 Synchronizing multiple devices
2.9.1 Internal synchronisation
For multiple device operation the DEWE-ORION-0824-20x is equipped with an additional synchronization
connector. A standard 10-pin connector with 1.27 mm flat ribbon cable is available for easy connection
between the boards. To reduce electromagnetic influences because of the very high frequency at this
synchronization bus, IEEE 1394 compatible LVDS (low voltage difference signals) are used.
The LVDS interface is current-based. Therefore the last board has to be terminated. This can be done with a
switch, positioned directly below the sync connector.
If you use only one DEWE-ORION-0824-20x in your system, the board has to be terminated.
Termination on
Termination off
DEWE-ORION-0824 DEWE-ORION-0824 DEWE-ORION-0824 DEWE-ORION-0824 DEWE-ORION-0824
Termination off
Slave
Termination on
Master