CS61581
2.14 Control Register 1 SH (CR2.0 = 1): Address 0x10
7 (MSB)
TAOS
6
LLOOP
5
RLOOP
4
LEN2
3
LEN1
2
LEN0
1
RSVD
0 (LSB)
LOS
TAOS
LLOOP
RLOOP
LEN [2:0]
RSVD
LOS
Transmit All Ones Select
When TAOS = 1, all ones are transmitted at the TCLK frequency
Local Loopback
When LLOOP = 1, data input at TPOS/TNEG (TDATA) is internally looped back and output on
RPOS/RNEG (RDATA). TCLK is routed to RCLK, through the jitter attenuator, if activated.
Remote Loopback
When RLOOP = 1, clock and data recovered by the receiver are sent back through the transmit
path and retransmitted. The clock and data are routed through the jitter attenuator, if activated.
Line Length Selection
Allows selection of a variety of transmit pulse shapes.
See Table 1 for details.
Note that the selection of T1 or E1 pulse shapes determines the operation of the device. When
MATCHZ is set to “1” the transmitter’s output impedance changes according to the pulse se-
lected. For T1 pulses, the encoders and decoders are set to B8ZS, and the QRSS data pattern
is 220-1 with 14 consecutive zeros, max. For E1 pulses, the encoders and decoders are set to
HDB3, and the QRSS data pattern is 215-1.
This bit is reserved.
Loss Of Signal
LOS = 1 when the loss of signal criteria have been met (175 zeros).
LOS = 0 when a valid signal is being received.
An interrupt will occur when LOS changes state unless a “1” is written to LOS disabling the in-
terrupt.
DS211PP8
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