Rx to Tx Loopback

This application is for diagnostic purposes only. It loops all the receive data from all timeslots back to the transmitting port. This application is used in conjunction with a Bit Error Rate Test to verify the operation of Cards and Laptop units.

• Transmit:
  
  Transmits the data received on same card.
  
  
• Stop Rx:
  
  Clicking this will stop receiving the data coming from the other card. Clicking on this button will end the process of looping back the data.
  
  
• Card Selection:
  
  Selects the card on which, the loopback will be activated.
  
  
• Close:
  
  Will exit the application.

Example

• Cross Connect card 1 to card 2 with a cross over cable. Set card1 to Rec Clock and Card 2 to Int Clk.
  
  
• Go to Intrusive Test and click on Rx-to-Tx Loopback. Select the card #1. and click on transmit.
  
  
• Using Card 2 open the Bit Error Rate (BER) application under Intrusive test. Click Restart on BERT and observe the following:
  
  Pat Sync
  No Errors
  No Loss of Sync
  
  On the BERT screen insert 4 to 5 errors. Observe the "Total Errors" count increase on BERT page as you insert errors. There is a 2 second delay due to the buffer, built into the software.