MPC8280 datasheet(1061/1386 Pages) FREESCALE

1061 / 1386 page

MPC8280 PowerQUICC II Family Reference Manual, Rev. 1

Freescale Semiconductor

32-1

Chapter 32

ATM AAL1 Circuit Emulation Service

NOTE

The functionality described in this chapter is not available on the MPC8270.

Refer to www.freescale.com for the latest RAM microcode packages that

support enhancements.

This chapter describes implementation of circuit emulation service (CES) using ATM adaptation layer

type 1 (AAL1) on the MPC8280 and should be used as a supplement to Chapter 31, “ATM Controller and

AAL0, AAL1, and AAL5.”

32.1

Features

The AAL1 CES features on the MPC8280 are as follows:

•

AAL1

— Reassembly

– Reassembles PDU directly to external memory

– Supports partially filled cells (configurable on a per-VC basis)

– Sequence number (SN) protection (CRC-3 and parity) check

– Implements a 3-step SN algorithm

– Detects and handles lost or misinserted cell

– Maintains bit count integrity (dummy cell insertion)

– Dummy cell contents can be programmed by the user (per FCC)

– Pointer verification in structured AAL1 cell format

– Automatic synchronization using the structured pointer during reassembly

– SRTS (synchronous residual time stamp) gathering on every cycle (8 cells) in unstructured

AAL1

– Statistics gathering on a per-VC basis:

– AAL1 valid cell count

– AAL1 lost cell count

– AAL1 misinserted cell count

– AAL1 pointer mismatch/parity error

– AAL1 Rx buffer pre-overflow

— Segmentation

– Segment PDU directly from external memory

MPC8280 Datasheet(PDF) 1061 Page - Freescale Semiconductor, Inc