Quatech QSC(LP)-300 user manual

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Full Duplex
Half Duplex using RTS
Half Duplex using DTR
Auto Toggle

Receivers are only enabled when not

When NOT Tranmitting transmitting. In a Half Duplex mode, you will not receive what you transmit.

RS-422/485 Duplex Mode

Transmitters and receivers are always enabled; ports can send and receive simultaneously. Used in four-wire communication.

RTS is set to enable the transmitters.

Used in two-wire communication.

DTR is set to enable the transmitters.

Used in two-wire communication

Hardware automatically enables the transmitters when transmitting. Transmitters will turn off three bit-times after the last stop bit of the last character, regardless of baud rate. Used in two-wire communication.

8.To summarize the RS-422/485 output drivers enable options: The QSC(LP)-200/300’s ports may be configured for either full duplex or half duplex operation with this option. The default setting is the RS-422/485 ports are configured for full duplex operation with the RS-422/485 output drivers always enabled. In half duplex mode, the RS-422/485 transmitter may be enabled and disabled via the RTS (request to send) or DTR (data terminal ready) signals, or in auto-toggle mode, set to enable only when data is being transmitted. Both RTS and DTR are controlled through the Modem Control Register of the 16750.

9.Click the "Port Settings" tab and then click the "Advanced" button. The QSC(LP)-200/300 driver will display a custom Advanced Port Settings control, which allows the ports UART compatibility mode and FIFO threshold levels to be configured. The threshold values of full-scale for the transmit buffer and ¾-scale for the receive buffer are optimal for most applications. Note that the FIFO option for each of the QSC(LP)-200/300's four ports is configured independently.

Quatech QSC(LP)-200/300 User's Manual

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Contents QSCLP-200/300 Date of Purchase Model Number Page Declaration of Conformity External Connections IND Option --- Surge Suppression UpgradeGeneral Information PCI Resource MapSpecifications Troubleshooting Features QSCLP-200/300 Product Series SummarySignal Connections Hardware Configuration1 AUX1,2,3,4 pins 3 and 4, 7 and 8, 11 and 12, 15 Force High-Speed Uart Clock X8, pins 17 Hardware Installation Jumper/connector locationsWindows Configuration Windows MillenniumWindows Windows Page Windows Windows NT Viewing Resources with Device Manager AdapterPage Changing Resource Settings with Device Manager RS-422/485 Serial AdapterData Rate Multiplier Page Page OS/2 Other Operating SystemsDOS and other operating systems QTPCI.EXE QTPCI.EXE Expert Mode display Rclk DTR/DSR or RTS/CTS OperationRTS/CTS Handshake TclkAUXIN/AUXOUT Loopback Termination Resistors RS-422/485 Termination44 connector definitions RS-422/485 Peripheral ConnectionAUXOUT+ Auxout AUXIN+ Auxin GND Base Address and Interrupt Level IRQ Port Address RangeSpecifications Computer will not boot up QSCLP-200/300 Revision November 940-0146-114