B&B Electronics DSC-200_300 - Manual - Manual (Page 35)

7 External Connections
The DSC-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 (TCLK), and the AUXIN signal (for loopback). Either half-duplex or full-duplex operation
can be selected for each communications channel. Auto-Toggle is also jumper selectable .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.
Configuration is done using jumpers J10 through J23 for interface signal routing. Each
jumper block provides the same functions for its particular channel. All below examples are for
Channel 1. Channel 2 is the same but different sets of jumpers. See Figure 15 for Channel 2
jumpers.
J17-23 Port 2
J10-16 Port 1
Signal routing Channel
Figure 15 --- Jumper/Channel correspondence
7.1 RTS/CTS Handshake
Transmission of RTS, combined with reception of CTS, allows for hardware handshaking
(data flow control) between the UART and the external device. RTS is transmitted on AUXOUT
by not connecting pins 1 and 2 of the jumper blocks J11-12. CTS is received on AUXIN by not
connecting pins 1 and 2 of the jumper block J10. If RTS/CTS handshaking is not desired, the
RTS output can be looped back to the CTS input by connecting pins 1 and 2 of the jumper block
J10. Figure 16 shows how to select the RTS/CTS mode.
Transmit RTS on AUXOUT
Receive CTS on AUXIN
Loopback RTS to CTS
Jumpers J10-12
CTS0_SEL
AUX0_SEL0
AUX0_SEL1
J10
J11
J12
CTS0_SEL
AUX0_SEL0
AUX0_SEL1
J10
J11
J12
Figure 16 --- RTS/CTS selection
Quatech DSC-200/300 User's Manual 33