82P2821BH IDT, Integrated Device Technology Inc, 82P2821BH Datasheet - Page 47

• Manufacturer Part Number: 82P2821BH
• Manufacturer: IDT, Integrated Device Technology Inc

Specifications of 82P2821BH

• Number Of Transceivers: 1
• Screening Level: Industrial
• Mounting: Surface Mount
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Lead Free Status / RoHS Status: Not Compliant

3.5.4
ERATION
3.5.4.1 Alarm Indication Signal (AIS) Detection
the transmit system side meets certain criteria, AIS is declared or
cleared. In T1/J1 mode, the criteria are in compliance with ANSI T1.231.
In E1 mode, the criteria are in compliance with ITU G.775 or ETSI
300233, as selected by the LAC bit (b7, LOS,...). Refer to Table-20 for
details.
STAT1,...) will be set. A transition from ‘0’ to ‘1’ on the LAIS_S bit (b6,
STAT1,...) or any transition (from ‘0’ to ‘1’ or from ‘1’ to ‘0’) on the LAIS_S
bit (b6, STAT1,...) will set the LAIS_IS bit (b6, INTS1,...) to ‘1’, as
selected by the AIS_IES bit (b6, INTES,...). When the LAIS_IS bit (b6,
INTS1,...) is ‘1’, an interrupt will be reported by INT if not masked by the
LAIS_IM bit (b6, INTM1,...).
STAT1,...) will be set. A transition from ‘0’ to ‘1’ on the SAIS_S bit (b7,
STAT1,...) or any transition (from ‘0’ to ‘1’ or from ‘1’ to ‘0’) on the
SAIS_S bit (b7, STAT1,...) will set the SAIS_IS bit (b7, INTS1,...) to ‘1’,
as selected by the AIS_IES bit (b6, INTES,...). When the SAIS_IS bit
(b7, INTS1,...) is ‘1’, an interrupt will be reported by INT if not masked by
the SAIS_IM bit (b7, INTM1,...).
by the RMFn or TMFn pin. Refer to Section 3.5.6 Error Counter and
Section 3.5.7 Receive /Transmit Multiplex Function (RMF / TMF) Indica-
tion respectively.
Table-20 AIS Criteria
Functional Description
IDT82P2821
AIS Declaring
AIS Clearing
AIS is monitored in both the receive path and the transmit path.
When the mark density in the received data or in the data input from
When AIS is detected in the receive path, the LAIS_S bit (b6,
When AIS is detected in the transmit path, the SAIS_S bit (b7,
AIS may be counted by an internal Error Counter or may be indicated
ALARM INDICATION SIGNAL (AIS) DETECTION AND GEN-
Less than 3 zeros are received in each of two
consecutive 512-bit data streams.
3 or more zeros are received in each of two
consecutive 512-bit data streams.
ITU G.775 for E1 (LAC = 0)
Less than 3 zeros are received
in a 512-bit data stream.
3 or more zeros are received in
a 512-bit data stream.
ETSI 300233 for E1 (LAC = 1)
21(+1) CHANNEL HIGH-DENSITY T1/E1/J1 LINE INTERFACE UNIT
47
3.5.4.2 (Alarm Indication Signal) AIS Generation
transmit path.
AIS will be generated automatically once LLOS is detected. When the
ASAIS_SLOS bit (b3, AISG,...) is set, AIS will be generated automati-
cally once SLOS is detected. When AIS is generated, RDn or RDPn/
RDNn output all ‘1’s. RCLKn (if available) outputs XCLK.
AIS will be generated automatically once LLOS is detected. When the
ALAIS_SLOS bit (b1, AISG,...) is set, AIS will be generated automati-
cally once SLOS is detected. When AIS is generated, TTIPn/TRINGn
output all ‘1’s.
direction, the priority of pattern generation is higher. The generated
pattern will overwrite automatic AIS. Refer to Section 3.5.5.1 Pattern
Generation for the output data and clock.
AIS can be generated automatically in the receive path and the
In the receive path, when the ASAIS_LLOS bit (b2, AISG,...) is set,
In the transmit path, when the ALAIS_LLOS bit (b0, AISG,...) is set,
AIS generation uses XCLK
If pattern (including PRBS, ARB and IB) is generated in the same
1. XCLK is derived from MCLK. It is 1.544 MHz in T1/J1 mode or 2.048 MHz
in E1 mode.
Less than 9 zeros are received in a 8192-bit stream, i.e., less
than 99.9% of marks in a period of 5.3 ms are received.
9 or more zeros are received in a 8192-bit data stream.
ANSI T1.231 for T1 (LAC = 0 or 1)
1
as reference clock.
February 6, 2009