Quatech SSCLP-200, SSCLP-300, DSCLP-200, DSCLP-300 Half-Duplex/Full-Duplex/Auto-Toggle Selection

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7.5 Half-Duplex/Full-Duplex/Auto-Toggle Selection

Using jumper blocks J14 thru J16, the transmitters and receivers of each channel can be enabled and disabled by modem control signals. This allows operation in both half-duplex, full-duplex or Auto-Toggle modes.

The transmit drivers can be controlled by either the Data Terminal Ready (DTR) or the Request to Send (RTS) output from the UART. If a jumper is applied between pins 1 and 2 of jumper block J14, the drivers are enabled for TxD and AUXOUT when the UART's DTR signal is asserted. If a jumper is applied between pins 1 and 2 of jumper block J15, the drivers are enabled for TxD and AUXOUT when the UART's RTS signal is asserted. If neither of these jumpers is applied, the drivers remain enabled at all times. When disabled, the transmit drivers enter a high-impedance state.

The receivers can be controlled by the inverse of the transmit enable. If a jumper is applied between pins 1 and 2 of jumper block J16, the receivers for RxD and AUXIN will be disabled when the transmit drivers are enabled and vice-versa (based on the DTR or RTS connections on pins 1-2 of J14 and J15.

To operate in half-duplex DTR mode, apply jumpers between pins 1 and 2 of jumper blocks J14 and J16. To operate in half-duplex RTS mode, apply jumpers between pins 1 and 2 .of jumper blocks J15 and J16

To operate in full-duplex mode, leave the jumpers in their factory default locations, installed in the spare locations of J14-16 only. The drivers and receivers are always enabled in full-duplex mode. For Auto-Toggle, apply jumpers between pins 1 and 2 of jumper blocks J14 and J15. Figure 20 shows how to select half-, full-duplex or Auto-Toggle operation.

WARNING:

When operating in half-duplex mode, the transmitter drivers must be disabled before receiving any data. Failure to do so may result in multiple active output drivers being connected together, which may cause damage to the board, the computer, and the external device.

DSCLP/SSCLP-200/300 User's Manual

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Contents DSCLP/SSCLP-200/300 Warranty Information Iii Manufacturers Address Manufacturers NameApplication of Council Directive Standards to which Conformity is DeclaredHardware Installation Address Map and Special Registers Hardware ConfigurationRS-422 or RS-485 Signal Line Termination Base Address and Interrupt Level IRQHalf-Duplex/Full-Duplex/Auto-Toggle Selection Page General Information Jumpers J6-J9 Full-duplex/Half-duplex Operation Signal ConnectionsRight Card Edge Jumpers Jumpers J10-J23 define the options for this card1 CTS0SEL, CTS1SEL J10 Force High-Speed Uart Clock X2, X4, or X8 J3, 4 Enable Scratchpad Register SPAD, J2Clock Rate and Optional Registers Clock multiplier jumper options Jumper/connector locations Hardware InstallationChannel Address Range Interrupt Status Register Enabling the Special RegistersDlab Bit Spad Jumper Register selected for Bit DescriptionQuatech Modem Control Register Quatech Modem Control RegisterWrite Read Options RegisterBit Name Description Clock Rate Uart Clock Maximum Data Multiplier Frequency Clock Rate MultiplierWindows Millennium Windows ConfigurationsWindows Windows Page Windows Windows NT Viewing Resources with Device Manager Two-Port RS-422/RS485 Serial Adapter Page DSCLP-200/300 Two-Port RS-422/485 Serial Adapter Page Page Page Page DOS and other operating systems Other Operating SystemsOS/2 QTPCI.EXE QTPCI.EXE Expert Mode display Jumper/Channel correspondence External ConnectionsRclk RTS/CTS HandshakeAUXIN/AUXOUT Loopback TclkHalf-Duplex/Full-Duplex/Auto-Toggle Selection Half/full-duplex and Auto-Toggle selection RS-422/485 Line termination resistance values Termination ResistorsRS-422/485 Peripheral Connection DSCLP-200/300 connector definitionsINTA# PCI Resource MapWith 64-byte FIFOs optional SpecificationsCannot communicate with other equipment TroubleshootingComputer will not boot up DSCLP/SSCLP-200/300
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