PM4314 QDSX
DATA SHEET
PMC-950857
ISSUE 5
QUAD T1/E1 LINE INTERFACE DEVICE
RXAISEN:
When RXAISEN is set to logic 1, an AIS is presented on the RDD/RDP[X]
and RDN[X] outputs. When RDD[X] is enabled, RDD[X] will be held always
high. If RDP[X] and RDN[X] are enabled, an alternating ones pattern (i.e. a
sequence of AMI coded ones) will be presented on RDP and RDN. Note that
the RDPINV and RDNINV bits will invert the inserted AIS signal in the same
way as other data. When RXAISEN is set to logic 0, RDD/RDP[X] and
RDN[X] carry data normally.
TXAISEN:
When the TXAISEN bit is set to logic one, an AIS signal is inserted on
TXTIP[X] and TXRING. This AIS signal consists of an AMI-encoded all-ones
sequence. When TXAIS is set to logic zero, TXTIP[X] and TXRING[X] carry
data as normal.
DIALB:
The DIALB bit selects the diagnostic digital loopback mode, where the
transmit data stream is connected to the receive data stream. When DIALB
is set to logic 1, the diagnostic digital loopback mode is enabled. When DIALB
is set to logic 0, the diagnostic digital loopback mode is disabled.
DMLB:
The DMLB bit enables the diagnostic metallic loopback mode, where the
digital, RZ positive and negative sliced versions of the analog signals output
on the TXTIP[X] and TXRING[X] pins from XPLS are internally connected to
the receive positive and negative pulse inputs of CDRC. When DMLB is set
to logic 1, the diagnostic metallic loopback mode is enabled. When DMLB is
set to logic 0, the diagnostic metallic loopback mode is disabled. Because
diagnostic metallic loopback is essentially a zero-line-length loopback, the 0’-
110’ line build out should be selected when using DMLB in T1 operation.
LINELB:
The LINELB bit selects the line loopback mode, where the data input on
RXTIP[X] and RXRING[X] is passed through the CDRC and then through
DJAT before being retransmitted on TXTIP[X] and TXRING[X] respectively.
When LINELB is set to logic 1, the line loopback mode is enabled. When
LINELB is set to logic 0, line loopback mode is disabled. Line loopback
should not be enabled in the QDSX unless DJAT is enabled in the transmit
path.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
64
PMC [ PMC-SIERRA, INC ]
