Quatech RS-422/485, MPA-200/300 user manual Circuit CD DTE Ready DTR Connector Notation +DTR,-DTR

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CIRCUIT CD - DTE READY (DTR)

￿CONNECTOR NOTATION: +DTR,-DTR

￿DIRECTION: To DCE

This signal controls the switching of the DCE to the communication channel. The DTE will generate this signal to prepare the DCE to be connected to or removed from the communication channel.

CIRCUIT LL - LOCAL LOOPBACK (LL)

￿CONNECTOR NOTATION: LLBK

￿DIRECTION: To DCE

This signal provides a means whereby a DTE may check the functioning of the DTE/DCE interface and the transmit and receive sections of the local DCE.

Note:

The local loopback and remote loopback signals are optional and are omitted from the DCE configuration of the MPA-200. Since testing will never occur for this configuration, the test mode signal will always be in the OFF condition for the DCE. These three test signals follow the EIA-423-A standard while the remaining signals follow the EIA-422-A standard.

CIRCUIT RL - REMOTE LOOPBACK (RL)

￿CONNECTOR NOTATION: RLBK

￿DIRECTION: To DCE

This signal provides a means whereby a DTE or a facility test center may check the transmission path up to and through the remote DCE to the DTE interface and the similar return transmission path.

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Quatech Inc., MPA-200/300 Manual

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Contents QUATECH, INC MPA-200/300Page Warranty Information Page Compliances Electromagnetic Emissions Table of Contents Quatech Inc., MPA-200/300 Manual Introduction MPA-200 board drawing IRQ DMA/DRQ Hardware InstallationSCC General Information Accessing the registers RR1 RR0RR2 RR3WR1 WR0WR2 WR3Baud Rate Generator Programming SCC Data Encoding Methods J4 Interrupt Configuration Jumper Block ConfigurationsJ5 & J6 Interrupt Level Selection IRQ3 IRQ4 IRQ5 IRQ6 IRQ7J10 Transmit DMA Channel Selection IRQ10 IRQ11 IRQ12 IRQ14 IRQ15J7 Line Driver Control Selection J11 Receive DMA Channel SelectionSynca Rlen OUT J8 Synca to Rlen controlBase Address = 3F8H AddressingPage Interrupts Direct Memory Access Page Reqa Configuration Register D0 -TXSRC, Transmit DMA Source D1 -RXSRC, Receive DMA SourceTM ST Llen Rlen Rcken Tcken Rxden Txden Communications RegisterD0 -TRANSMITTER Enable D1 -RECEIVER EnableDTE / DCE Configuration Rrclk Rtclk Trxca Tclk Ttclk DTE ConfigurationDCE Configuration DCE Clock Configuration External Connections CTS Ctsa +DSR Dcda DTR DTR/REQA DSR Dcda +RRCLK Trxc Test ModeTest Mode Null-Modem Cables Circuit CC Data SET Ready DSR Connector Notation +DSR,-DSR Circuit AB Signal Ground Connector Notation DgndConnector Notation +TXD,-TXD Connector Notation +RXD,-RXDConnector Notation +RRCLK,-RRCLK Connector Notation +RTCLK,-RTCLKCircuit CA Request to Send RTS Connector Notation +RTS,-RTS Circuit CB Clear to Send CTS Connector Notation +CTS,-CTSCircuit RL Remote Loopback RL Connector Notation Rlbk Circuit CD DTE Ready DTR Connector Notation +DTR,-DTRCircuit LL Local Loopback LL Connector Notation Llbk Circuit TM Test Mode TM Connector Notation Test Mode Specifications MPA-200/300 Version March
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