PM5366-PI datasheet(111/267 Pages) PMC

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PRELIMINARY

PM5366 TEMAP-84

DATASHEET

PMC-2010672

ISSUE 1

HIGH DENSITY 84/63 CHANNEL VT/TU MAPPER

AND M13 MULTIPLEXER

PROPRIETARY AND CONFIDENTIAL

The tributary trace message of each tributary is extracted form the J2 (J1 in TU3

mode) byte. It is written to the internal buffer corresponding to the tributary. The

internal buffer may behave as a simple circular buffer, or optionally, be

synchronized to the framing pattern embedded in the message. For a 16-byte

trail trace identifier, the first byte is identified by a logic one in the most significant

bit. For a 64-byte tributary trace message, the last two bytes are set to the ASCII

characters for carriage-return (CR) and linefeed (LF).

An extracted message is declared the accepted message, if it is received

unchanged for 3 multiframes. The accepted message is compared with the

locally provisioned expected message. A tributary trace identifier mismatch

alarm (TIM) is asserted when the accepted and expected messages differ.

Conversely, TIM is negated when the messages are identical. An interrupt is

optionally generated upon a change in the TIM state. Messages of all-zeros

bytes cannot become accepted and, therefore, have no effect on the TIM state.

The RTTB also monitors for tributary trace unstable conditions. Each time a

tributary trace message that is received differs from the previous message, the

unstable counter is incremented by one. The tributary trace unstable alarm (TIU)

is asserted when the unstable counter reaches eight. The unstable counter is

cleared and the unstable alarm negated when the extracted message remains

unchanged for enough multiframes to meet the acceptance criteria. An interrupt

is optionally generated upon a change in the TIU state.

9.25 Receive Tributary Bit Asynchronous Demapper (RTDM)

Each one of three Receive Tributary Demappers (RTDM) demaps up to 28 T1 or

21 E1 bit asynchronous mapped signals from an STS-1 SPE, TUG3 within a

STM-1/VC4 or STM-1 VC3 payload. The bit asynchronous T1 mapping consists

of 104 octets every 500 µs (2 KHz) and is shown in Table 3. The bit

asynchronous E1 mapping consists of 140 octets every 500us and is shown in

Table 4.

PM5366-PI Datasheet(PDF) 111 Page - PMC-Sierra, Inc