Quatech Asynchronous Communications Adapter DSC-200/300 User Manual

Quatech Asynchronous Communications Adapter DSC-200/300 User Manual Manual pdf 31 page image

8.3 XCLKThis is the output clock signal used by the transmitter portion of the UART. It isgenerally connected to the UART's own receive clock input (RCLK). This is done byconnecting pins 3 and 6 of the jumper block. If desired, XCLK can be transmitted to anexternal source over the AUXOUT line by connecting pins 5 and 6 of the jumper block.Figure 21 shows how to select the XCLK mode.Loopback XCLK to RCLK Transmit XCLK on AUXOUTCTSAUXINXCLKRTSAUXOUTRCLK123654 CTSAUXINXCLKRTSAUXOUTRCLK123654Jumpers J5, J7Figure 21 --- XCLK selection8.4 AUXIN/AUXOUT LoopbackThe AUXIN signal is an input from the external device, and connecting it to theAUXOUT signal provides for a loopback mode of operation. In other words, whateversignal is transmitted by the external device over the AUXIN line will be fed back to theexternal device over the AUXOUT line. This mode is accomplished by connecting pins2 and 5 of the jumper block. Figure 22 shows how to select this loopback mode.Loopback AUXOUT to AUXINCTSAUXINXCLKRTSAUXOUTRCLK123654Jumpers J5, J7Figure 22 --- AUXIN/AUXOUT loopbackQuatech DSC-200/300 User's Manual 31