XRT75L03 Datasheet, PDF (90/92 Pages) Exar Corporation – THREE CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH JITTER ATTENUATOR

XRT75L03
REV. 1.0.4
THREE CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH JITTER ATTENUATOR
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 TClk_n.TAOS data path is shown in Figure 29. TAOS does not
operate in Analog loopback or Remote loopback modes. It will function in Digital loopback mode.
FIGURE 29. 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
87