External Connections - Quatech QSC-200 User Manual

8 External Connections

The QSC-200/300 provides four differential communication signals per channel. The
two output signals are Transmit Data (TxD) and Auxiliary Output (AUXOUT). The two input
signals are Receive Data (RxD) and Auxiliary Input (AUXIN). A ground signal is also provided.
The available input signals for AUXIN are Clear To Send (CTS) and the Receive Clock
(RCLK). The available output signals for AUXOUT are Request To Send (RTS), the Transmit
Clock (XCLK), and the AUXIN signal (for loopback). Either half-duplex or full-duplex
operation can be selected for each communications channel. If half-duplex operation is selected,
one of the UART's signals (either DTR or RTS) is used to enable the transmitter drivers. The
inverse of the transmitter enable can be used to enable the receiver drivers.
Factory-installed resistors allow for signal line termination in compliance with the
RS-422 and RS-485 standards. The desired termination can be selected or removed per port by
applying a jumper.
Configuration is done using jumpers J1 through J8 for termination selection, and jumpers
J9 through J16 for interface signal routing. Each jumper block provides the same functions for
its particular channel.
XCLK
AUXOUT
Tx ENABLE
Tx ENABLE
Tx ENABLE
Quatech QSC-200/300 Users Manual
Channel
Port 1
Port 2
Port 3
Port 4
Figure 17 --- Jumper/Channel correspondence
3
6 RCLK
2
AUXIN
5
RTS 4 1
CTS
3
6
Rx ENABLE
2 RTS
5
4 1 DTR
Figure 18 --- Pin out of jumpers J9-J16
Termination Signal routing
J1, J2
J3, J4
J5, J6
J7, J8
Jumpers
J9, J11, J13, J15
Jumpers
J10, J12, J14, J16
Half-duplex
if 3-6 shorted
J9, J10
J11, J12
J13, J14
J15, J16
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