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STANDARD PRODUCT
PM8315 TEMUX
DATASHEET
PMC-1981125
ISSUE 7
HIGH DENSITY T1/E1 FRAMER WITH
INTEGRATED VT/TU MAPPER AND M13 MUX
PROPRIETARY AND CONFIDENTIAL
207
Figure 41
- Per-Channel Loopback
T1/E1-FRMR
Framer:
Frame
Alignment,
Alarm
Extraction
ELST
Elastic
Store
ISIF
Ingress
Interface
FRAM
Framer/
Slip Buffer
RAM
ID[1:28]
ICLK[1:28]/ISIG[1:28]
IFP[1:28]
RxCLK[1:28]
RxD[1:28]
TJAT
Digital Jitter
Attenuator
T1-XBAS/E1-TRAN
BasicTransmitter:
Frame Generation,
Alarm Insertion,
Signaling
ti
I
Line Coding
ESIF
Egress
Interface
TRANSMITTER
TxD[1:28]
TxCLK[1:28]
ED[1:28]
CTCLK*
ECLK[1:28]/EFP[1:28]/
ESIG[1:28]
CEFP*
CECLK*
RJAT
Digital Jitter
Attenuator
TOPS
Timing Options
RECEIVER
MUX
TPSC
Per-DS0
Serial
Controller
Per- DS0 Loopback
12.9 DS3 Loopback Modes
The TEMUX 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