XRT73L02M Datasheet, PDF (44/46 Pages) Exar Corporation – TWO CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT

XRT73L02M
xr
TWO CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT
REV. 1.0.0
During the remote loop back mode, if the jitter attenuator is selected in the transmit path, the receive data after
the Clock and Data Recovery Block is looped back to the transmit path and passed through the jitter attenuator
using RxClk as the transmit timing.
NOTE: Input signals on TxClk, TPOS and TNEG are ignored during Remote loop back.
FIGURE 27. REMOTE LOOPBACK
TCLK
TPDATA
TNDATA
1
HDB3/B3ZS
ENCODER
TIMING
CONTROL
Tx
TTIP
TRING
RCLK
RPOS
RNEG
1
HDB3/B3ZS
DECODER
1 _{if enabled}
2 _{if enabled and selected in either Receive or}
Transmit path
DATA &
CLOCK
RECOVERY
RTIP
Rx
RRING
8.3 TRANSMIT ALL ONES (TAOS):
Transmit All Ones (TAOS) can be set either in Hardware mode by pulling the TAOS_n pins “High” or in Host
mode by setting the TAOS_n control bits to “1” in the Channel control registers. When the TAOS is set, the
Transmit Section generates and transmits a continuous AMI all “1’s” pattern on TTIP_n and TRING_n pins. The
frequency of this “1’s” pattern is determined by TxClk_n.TAOS data path is shown in Figure 29.
FIGURE 28. TRANSMIT ALL ONES (TAOS)
TCLK
TPDATA
TNDATA
1
HDB3/B3ZS
ENCODER
TIMING
CONTROL
TAOS
TTIP
Tx
Transmit All 1'
TRING
RCLK
RPOS
RNEG
1
HDB3/B3ZS
DECODER
DATA &
CLOCK
Rx
RECOVERY
1 _{if enabled}
2 _{if enabled and selected in either Receive or}
Transmit path
RTIP
RRING
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