XRT83SH38 View Datasheet(PDF) - Exar Corporation
Part Name
Description
MFG CO.
'XRT83SH38' PDF : 78 Pages View PDF
XRT83SH38
8-CHANNEL T1/E1/J1 SHORT-HAUL LINE INTERFACE UNIT
REV. 1.0.7
4.5.1 ATAOS (Automatic Transmit All Ones)
If ATAOS is selected by programming the appropriate global register, an AMI all ones signal will be transmitted
for each channel that experiences an RLOS condition. If RLOS does not occur, the ATAOS will remain inactive
until an RLOS on a given channel occurs. A simplified block diagram of the ATAOS function is shown in
Figure 20.
FIGURE 20. SIMPLIFIED BLOCK DIAGRAM OF THE ATAOS FUNCTION
TAOS
TTIP
Tx
TRING
ATAOS
RLOS
4.5.2 QRSS Generation
The XRT83SH38 can transmit a QRSS random sequence to a remote location from TTIP/TRING. The
polynomial is shown in Table 11.
TABLE 11: RANDOM BIT SEQUENCE POLYNOMIALS
RANDOM PATTERN
T1
E1
QRSS
220 - 1
215 - 1
4.5.3 T1 Short Haul Line Build Out (LBO)
The short haul transmitter output pulses are generated using a 7-Bit internal DAC (6-Bit plus the MSB sign bit).
The line build out can be set to interface to five different ranges of cable attenuation by programming the
appropriate channel register. The pulse shape is divided into eight discrete time segments which are set to
fixed values to comply with the pulse template. To program the eight segments individually to optimize a
special line build out, see the arbitrary pulse section of this datasheet. The short haul LBO settings are shown
in Table 12.
TABLE 12: SHORT HAUL LINE BUILD OUT
LBO SETTING EQC[4:0]
RANGE OF CABLE ATTENUATION
08h (01000)
0 - 133 Feet
09h (01001)
133 - 266 Feet
0Ah (01010)
266 - 399 Feet
0Bh (01011)
399 - 533 Feet
0Ch (01100)
533 - 655 Feet
31
Share Link: 
