PM4341AT1XC
DATA SHEET
PMC-900602
ISSUE 7
T1 FRAMER/TRANSCEIVER
clock from network interface) as the jitter reference. Also, since T1XC #2's elastic
store is bypassed, the TRSLIP bit in the Receive Options register can be set to
provide a measure of the frequency difference between the network clock and
the customer clock by monitoring the time interval between resulting slip
indications.
This application can be readily modified to provide additional features by simply
changing the T1XC configurations via software. No external wiring changes are
necessary to support framing format conversion or to loop time the network
transmit data to the network receive recovered clock.
For example, to provide format conversion of a customer's SF-based equipment
to an ESF network, T1XC #1 would be programmed to receive and transmit ESF
formatted data, while providing superframe alignment indication on the
backplane frame pulse output (BRFPO). T1XC #2 would be programmed to
receive and transmit SF formatted data, while providing every second
superframe alignment indication on its BRFPO.To provide loop timing of the
network transmit to the network receive clock, T1XC #2 would be programmed to
use the elastic store, thereby providing the slip buffering to handle the frequency
difference between the network and customer equipment clocks.T1XC #1 would
be programmed to use its RCLKO for the transmitter clock instead of the input
BTCLK.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
9
PMC [ PMC-SIERRA, INC ]
