STANDARD PRODUCT
PM5365 TEMAP
DATASHEET
PMC-1991148
ISSUE 3
HIGH DENSITY VT/TU MAPPER
AND M13 MULTIPLEXER
Figure 24: T1/E1 Diagnostic Digital Loopback
CTCLK*
TRANSMITTER
TOPS
ED[1:28]
ECLK[1:28]
ESIF
Egress
Timing Options
Interface
TJAT
TxCLK[1:28]
TxD[1:28]
Digital Jitter
Attenuator
Di agn ost i c Loopb ack
PMON
Performance
Monitor
RJAT
RxCLK[1:28]
RxD[1:28]
ISIF
Ingress
Interface
ID[1:28]
Digital Jitter
Attenuator
ICLK[1:28]
RECEIVER
12.5 DS3 Loopback Modes
The TEMAP provides three DS3 M13 multiplexer loopback modes to aid in
network and system diagnostics at the DS3 interface. The DS3 loopbacks can be
initiated via the µP interface whenever the DS3 framer/M13 multiplexer is
enabled. The DS3 Master Data Source register controls the DS3 loopback
modes. These loopbacks are also available when the DS3 mux is used with the
DS3 mapper via the telecom bus interface.
DS3 Diagnostic Loopback
DS3 Diagnostic Loopback allows the transmitted DS3 stream to be looped back
into the receive DS3 path, overriding the DS3 stream received on the
RDAT/RPOS and RNEG/RLCV inputs. The RCLK signal is also substituted with
the transmit DS3 clock, TCLK. While this mode is active, AIS may be substituted
for the DS3 payload being transmitted on the TPOS/TDAT and TNEG/TMFP
outputs. The configuration of the receive interface determines how the
TNEG/TMFP signal is handled during loopback: if the UNI bit in the DS3 FRMR
register is set, then the receive interface is configured for RDAT and RLCV,
therefore the TNEG/TMFP signal is suppressed during loopback so that transmit
MFP indications will not be seen nor accumulated as input LCVs. If the UNI bit is
clear, then the interface is configured for bipolar signals RPOS and RNEG,
Proprietary and Confidential to PMC-Sierra, Inc. and for its Customers’ Internal Use
157
PMC [ PMC-SIERRA, INC ]
