ADTRAN DSU 5600 User Manual

1 0 DSU 5600 User Manual 61200.078L1-1Chapter 2. InstallationCarrier Detect (CD) - SW 6When this switch is in the down (normal) position, CarrierDetect (CD) is On any time customer data is being received andOff when the receive circuit is idle, (not carrying customer data).When this switch is in the up (On) position, CD is forced On allthe time.Data Set Ready (SR) - SW 7When this switch is in the down (On) position, Data Set Ready(SR) is forced On all the time. For the up (normal) position, SR isturned Off when the network is out of service or a test is inprogress.Remote Digital Loopback (RDL) - SW 8When this switch is in the down (enable) position, the DSU 5600accepts the industry standard V.54 Remote Digital Loopback(RDL) command from the far end of the circuit.When this switch is in the up (disable) position, the DSU 5600does not respond to a V.54 loopback command from the far endof the circuit.