Rainbow Electronics DS26519 - Manual (Page 105)

DS26519 16-Port T1/E1/J1 Transceiver
105 of 310
9.12.6.5 Dual Loopback
The inputs decoded from the receive LIU are looped back to the transmit LIU. The inputs from the transmit framer
are looped back to the receiver with the optional jitter attenuator. Dual Loopback is a combination of Local
Loopback and Remote Loopback 1. This loopback is invoked by setting the correct bits in the LIU Maintenance
Control Register (
LMCR ). This loopback is conceptually shown in Figure 9-31 .
Figure 9-31. Dual Loopback
Line
Driver Transmit
Framer
Optional
Jitter
Attenuator
Transmit
Digital
Transmit
Analog
TCLK
TSER
Receive
Framer
Optional
Jitter
Attenuator
Receive
Digital Receive
Analog
RCLK
RSER
RTIP
RRING
TTIP
TRING