STANDARD PRODUCT
PM4351 COMET
DATA SHEET
PMC-1970624
ISSUE 10
COMBINED E1/T1 TRANSCEIVER
Register 004H: Transmit Line Interface Configuration
Bit
Type
Function
Default
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
R/W
R/W
R/W
R/W
R/W
TJATBYP
TAISEN
TAUXP
TDATINV
TUNI
0
0
0
0
0
X
0
X
Unused
TRISE
R/W
Unused
This register enables the transmit interface to generate the required digital output
waveform format.
TJATBYP:
The TJATBYP bit enables the transmit jitter attenuator's FIFO to be removed
from the transmit data path. When transmit jitter attenuation is not being
used, setting TJATBYP to logic 1 will reduce the latency through the
transmitter section by typically 40 bits.
TAISEN:
The TAISEN bit enables the interface to generate an unframed all-ones AIS
alarm on the TXTIP, TXRING and TDAT pins. When TAISEN is set to logic 1
and TUNI is set to logic 0, the bipolar TXTIP and TXRING outputs are forced
to pulse alternately, creating an all-ones signal; when TAISEN and TUNI are
both set to logic 1, the unipolar TDAT output is forced to all-ones. The
transition to transmitting AIS on the TXTIP and TXRING outputs is done in
such a way as to not introduce any bipolar violations.
The TAISEN bit only takes effect when the AISE bit of the XLPG
Control/Status register is logic 1.
The diagnostic loopback point is upstream of this AIS insertion point.
TAUXP:
The TAUXP bit enables the interface to generate an unframed alternating
zeros and ones (i.e. 010101...) auxiliary pattern (AUXP) on the TXTIP,
TXRING and TDAT pins. When TAUXP is set to logic 1 and TUNI is set to
PROPRIETARY AND CONFIDENTIAL
85
PMC [ PMC-SIERRA, INC ]
