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XRT94L33
3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC DATA SHEET
Rev.1.2.0.
215
2.2.7
TRANSMIT STS-3C POH PROCESSOR BLOCK (FOR ATM/PPP OVER STS-3C APPLICATIONS)
All outbound ATM cells that exit the Transmit ATM Cell Processor block will be routed to the Transmit STS-3c
POH Processor block, where they will be mapped into either STS-3c SPEs. Likewise, all outbound PPP
packets that exit the Transmit PPP Packet Processor block will be routed to the Transmit STS-3c POH
Processor block, where they will be mapped into STS-3c SPEs. The purpose of the Transmit STS-3c POH
Processor block is to accomplish the following.
To accept ATM cells from the Transmit ATM Cell Processor block and to map these cells into STS-3c
SPE (Synchronous Payload Envelope), or
To accept PPP packets from the Transmit PPP Packet Processor block and to map these packets into
STS-3c SPEs
To compute and insert the B3 (Path BIP-8) byte
To deliberately transmit an STS-3c SPE with an erred B3 byte (for testing purposes)
To source the J1, C2, G1, F2, H4, Z3, Z4 and Z5 bytes.
To automatically transmit the RDI-P (Path – Remote Defect) Indicator whenever (and for the duration
that) the corresponding Receive STS-3c POH Processor block declares the AIS-P, LOP-P, UNEQ-P,
TIM-P or PLM-P defect conditions.
To automatically transmit the RDI-P indicator whenever (and for the duration that) the corresponding
Receive ATM Cell Processor block declares the LCD defect condition.
To transmit the RDI-P Indicator upon Software Control.
To automatically transmit the REI-P (Path – Remote Error) Indicator anytime the corresponding Receive
STS-3c POH Processor block detects B3 byte errors in its incoming STS-3c SPE data-stream.
To transmit the REI-P indicator upon Software Control.
To transmit the AIS-P (Path – Alarm Indication Signal) Indicator upon Software Control.
To permit the user to transmit either 1 byte, 16 byte or 64 byte Path Trace Messages to the remote PTE.
To force “positive-stuff” pointer adjustments in the outbound STS-3c data-stream.
To force “negative-stuff” pointer adjustments in the outbound STS-3c data-stream.
To force single and continuous NDF (New Data Flag) events into the outbound STS-3c data-stream
To route its output data to the Transmit STS-3c TOH Processor block for further processing.
Figure 33 presents an illustration of the block diagram of the XRT94L33 Mapper IC, with the “Transmit STS-
3c POH Processor” block highlighted.