Lucent Technologies Inc.
Lucent Technologies Inc.
83
Preliminary Data Sheet
October 2000
T7630 Dual T1/E1 5.0 V Short-Haul Terminator (Terminator-II)
Alarms and Performance Monitoring
(continued)
4. The
SLIP
condition (FRM_SR3 bit 6 and bit 7).
SLIP is defined as the state in which the receive elastic store buffer’s write address pointer from the receive framer
and the read address pointer from the transmit CHI are equal
*
.
I
The negative slip (Slip-N) alarm indicates that the receive line clock (RLCK) - transmit CHI clock (TCHICK) mon-
itoring circuit detects a state of overflow caused by RLCK and TCHICK being out of phase-lock and the period of
the received frame being less than that of the system frame. One system frame is deleted.
I
The positive slip (Slip-P) alarm indicates the line clock (RLCK) - transmit CHI clock (TCHICK) monitoring circuit
detects a state of underflow caused by RLCK and TCHICK being out of phase-lock and the period of the
received frame being greater than that of the system frame. One system frame is repeated.
5. The
loss of framer receive clock
(LOFRMRLCK, pins 2 and 38).
In the framer mode, FRAMER = 0 (pin 41/141), LOFRMRLCK alarm is asserted high when an interval of
250 μs has expired with no transition of RLCK (pin 135/47) detected. The alarm is disabled on the first transition of
RLCK. In the terminator mode, FRAMER = 1 (pin 41/141), LOFRMRLCK is asserted high when SYSCK (pin 3/35)
does not toggle for 250 μs. The alarm is disabled on the first transition of SYSCK.
6. The
loss of PLL clock
(LOPLLCK, pins 39 and 143).
LOPLLCK alarm is asserted high when an interval of 250 μs has expired with no transition of PLLCK detected. The
alarm is disabled 250 μs after the first transition of PLLCK. Timing for LOPLLCK is shown in Figure 39.
5-6564(F)r.2
Figure 39. Timing for Generation of LOPLLCK (Pin 39/143)
7. Received
bipolar violation errors
alarm, FRM_SR3 bit 0.
This alarm indicates any bipolar decoding error or detection of excessive zeros.
8. Received
excessive CRC errors
alarm, FRM_SR3 bit 3.
In ESF, this alarm is asserted when 320 or more CRC-6 checksum errors are detected within a one second inter-
val. In CEPT, this alarm is asserted when 915 or more CRC-4 checksum errors are detected within a one second
interval.
* After a reset, the read and write pointers of the receive path elastic store will be set to a known state.
PLLCK
LOPLLCK
RCHICK
250
μ
s
250
μ
s