Quatech RS-485 user manual AUXIN/AUXOUT Loopback, AUXIN/AUXOUT loopback

Page 37

7.4 AUXIN/AUXOUT Loopback

The AUXIN signal is an input from the external device, and connecting it to the AUXOUT signal provides for a loopback mode of operation. In other words, whatever signal is transmitted by the external device over the AUXIN line will be fed back to the external device over the AUXOUT line. This mode is accomplished by connecting pins 1 and 2 of the jumper blocks J11 and J12. Figure 19 shows how to select this loopback mode.

Jumpers J11-13

J11

J12

J13

AUX0_SEL0 AUX0_SEL1

RCLK0_SEL

Loopback AUXOUT to AUXIN

Figure 19 --- AUXIN/AUXOUT loopback

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.

Quatech DSC-200/300 User's Manual

35

Page 36 Page 38
Image 37
Page 36 Page 38
Contents DSC-200/300 Date of Purchase Model Number Page Declaration of Conformity Changing Resource Settings with Device Manager IND Option --- Surge Suppression Upgrade2 AUX0SEL1,0, AUX1SEL1,0 J12,11,19,18 4 TGL0SEL1,0, TGL1SEL1,0 J15,14,22,21Half-Duplex/Full-Duplex/Auto-Toggle Selection External ConnectionsGeneral Information DSC-200/300 Product Series Summary FeaturesFull-duplex/Half-duplex Operation Signal ConnectionsJumpers J10-J23 define the options for this card RCLK0SEL, RCLK1SEL J13 1 CTS0SEL, CTS1SEL J10,17RXEN0SEL, RXEN1SEL J16 Clock Rate and Optional Registers Enable Scratchpad Register SPAD, J2Clock multiplier jumper options Hardware Installation Base Address and Interrupt Level IRQ Interrupt Status Register Enabling the Special RegistersQuatech Modem Control Register Quatech Modem Control RegisterBit Name Description Options RegisterRR1 RR0 Clock Rate MultiplierWindows Millennium Windows Windows Windows Windows NT Viewing Resources with Device Manager Quatech DSC-200/300 PCI Two-Port RS-422/RS485 Serial Adapter Adapter Data Rate Multiplier Application. This mode is useful for legacy Used when external handshaking or Page DOS and other operating systems OS/2QTPCI.EXE QTPCI.EXE Expert Mode display Jumpers J10-12 RTS/CTS HandshakeTclk RclkAUXIN/AUXOUT loopback AUXIN/AUXOUT LoopbackHalf/full-duplex and Auto-Toggle selection RS-422/485 Termination Termination ResistorsRS-422/485 Peripheral Connection DSC-200/300 connector definitionsPCI Resource Map Specifications Computer will not boot up
Top Page Image Contents