Datasheet

____________________________________________________ DS34T101, DS34T102, DS34T104, DS34T108
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Register Name:
LMCR
Register Description:
LIU Maintenance Control Register
Register Address:
base address + 0x08
Bit # 7 6 5 4 3 2 1 0
Name TAIS ATAIS LB2 LB1 LB0 TPDE RPDE TXEN
Default 0 0 0 0 0 0 0 0
Bit 7: Transmit AIS (TAIS). Alarm Indication Signal (AIS) is sent timed by T1CLK or E1CLK. The transmit clock
and data coming from the framer are ignored. See section 10.13.2.5.
0 = No
rmal operation
1 = Transmit unframed all-ones pattern (AIS) on TTIP/TRING.
Bit 6:
Automatic Transmit AIS (ATAIS). See section 10.13.2.5.
0 = No
rmal operation
1 = Automatically transmit AIS on the occurrence of an LIU LOS
Bits 5 to 3: Loopback Selection (LB[2:0] See Section 10.13.5 fo
r more details on each loopback.
LB2 LB1 LB0 Loopback Selection
0 0 0 No Loopback Selected
0 0 1 Remote Loopback 2 (includes Jitter Attenuator, See Section 10.13.5.3)
0 1 0 Analog Loopback (See Section 10.13.5.1)
0 1 1 Reserved
1 0 0 Local Loopback (includes Jitter Attenuator, See Section 10.13.5.2)
1 0 1
Dual Loopback – Remote Loopback 1 and Local Loopback (jitter attenuator is
included in Local Loopback, See Section 10.13.5.4)
1 1 0 Reserved
1 1 1 Reserved
Bit 2: Transmit Power-Down Enable (TPDE).
See section 10.13.2.8.
0 = Normal operation
1 = LIU transmitter powered down. TTIP/TRING outputs are high impedance..
Bit 1: Receiver Power-Down Enable (RPDE). See section 10.13.3.7.
0 = No
rmal
1 = LIU receiver powered down.
Bit 0: Transmit Enable (TXEN). This function can be overridden by the TXENABLE pin. See section 10.13.2.3.
0 = TTIP/TRING outputs are high impedance. The internal circuitry of the LIU transmitter is still active.
1 = TTIP/TRING outputs enabled.