STANDARD PRODUCT
PM4328 TECT3
DATASHEET
PMC-2011596
ISSUE 1
HIGH DENSITY T1/E1 FRAMER
AND M13 MULTIPLEXER
not available in payload loopback mode. The data flow in per-channel loopback
is illustrated in Figure 37.
Figure 37: Per-Channel Loopback
CTCLK*
TRANSMITTER
ED[1:28]
T1-XBAS/E1-TRAN
TOPS
ECLK[1:28]/EFP[1:28]/
ESIG[1:28]
ESIF
BasicTransmitter:
Timing Options
Egress
Interface
Frame Generation,
Alarm Insertion,
Signaling
CEFP*
TJAT
TxCLK[1:28]
TxD[1:28]
CECLK*
Digital Jitter
Attenuator
TPSC
Per-DS0
Serial
Trunk Conditioning
MUX
Line Coding
Controller
Per - DS0 Loopback
FRAM
Framer/
Slip Buffer
RAM
ELST
Elastic
Store
T1/E1-FRMR
ID[1:28]
ICLK[1:28]/ISIG[1:28]
IFP[1:28]
Framer:
RxCLK[1:28]
RxD[1:28]
RJAT
Frame
Digital Jitter
Attenuator
ISIF
Alignment,
Alarm
Ingress
Interface
Extraction
RECEIVER
12.9 DS3 Loopback Modes
The TECT3 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.
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,
PROPRIETARY AND CONFIDENTIAL
154
PMC [ PMC-SIERRA, INC ]
