MC92500ZQ 데이터 시트보기 (PDF) - Motorola => Freescale

부품명

상세내역

일치하는 목록

MC92500ZQ

ATM Cell Processor

Motorola => Freescale 

4. EXTERNAL MEMORY DESCRIPTION

4.1 MC92500 External Memory

The MC92500 uses external memory to store the data-

base (context information) relating to the processing of

cells on a per-connection basis. The MC92500 can ac-

cess External Memory with 16- or 32-bit data.

4.1.1 Memory Partitioning

The External memory is partitioned into several tables:

(see Figure 6)

• Ingress Billing Counters - consists of a record for

each active connection. The record contains the

cell counters that are used by the connection dur-

ing the normal Ingress cell flow. This table is dy-

namic and updated by the MC92500. The

microprocessor is responsible for collecting the

contents of the counters on a regular basis.

• Egress Billing Counters - consists of a record for

each active connection. The record contains the

counters that are used by the connection during the

normal Egress cell flow. This table is dynamic and

updated by the MC92500. The microprocessor is

responsible for collecting the contents of the

counters on a regular basis.

• Flags Table - consists of a record for each active

connection. The record contains OAM flags that

are used by all the connections during the normal

cell flow. This table is dynamic and updated by the

MC92500. The microprocessor is responsible for

checking the flags on a regular basis

• Context Parameters Table - consists of a record for

each active connection. The record contains con-

nection-specific information for processing and

routing the cells belonging to the connection.

• Ingress Policing Counters - consists of a record for

each active connection. The record contains the

counters that are used to record the results of the

UPC/NPC policing. This table is dynamic and up-

dated by the MC92500. The microprocessor is re-

sponsible for collecting the contents of the counters

on a regular basis.

• VC Table - contains a list of all the Ingress Connec-

tion Identifiers (ICIs) that have been defined by the

microprocessor as active Virtual Channel Connec-

tions. This table exists only if the Table Lookup

method of Address Compression is used with VC

Table Lookup enabled.

• Multicast Translation Table - contains the Egress

Connection Identifiers (ECIs) associated with the

multicast identifiers.

• OAM Table - contains the additional information

required to run OAM Performance Monitoring.

• VP Table(s) - each record contains an Ingress Con-

nection Identifier (ICI) that has been defined by the

microprocessor as an active connection. The size

and location of the VP Table(s) are determined by

the Link Register. If multiple links are supported,

each Link Register defines a separate VP Table.

The multiple VP Tables are not required to be con-

tiguous.

• Dump Vector Table - contains the dump vectors

describing the recent history of the cell processing.

This table is generally only used for debugging

purposes.

• Egress Link Counters - consists of a record for

each link. The record contains the cell counters that

are used by the link during the normal Egress cell

flow. This table is dynamic and updated by the

MC92500. The microprocessor is responsible for

collecting the contents of the counters on a regular

basis.

• Ingress Link Counters - consists of a record for

each link. The record contains the cell counters that

are used by the link during the normal Ingress cell

flow. This table is dynamic and updated by the

MC92500. The microprocessor is responsible for

collecting the contents of the counters on a regular

basis.

• Virtual Bucket Table - each record in this table con-

tains the information for the UPC/NPC enforce-

ment. This is not a physical table, but a virtual one.

Since the Parameters Table contains a full address

for the location of the Bucket record of each con-

nection, there is no need to put all the Bucket

records in consecutive physical locations. Although

the user can distribute the records in any manner.

MC92500

MOTOROLA

11

Share Link: