CN205862315U

CN205862315U - A kind of CAM structure based on FPGA

Info

Publication number: CN205862315U
Application number: CN201620611327.7U
Authority: CN
Inventors: 尹超; 赵鑫鑫; 李朋
Original assignee: Inspur Group Co Ltd
Current assignee: Shandong Inspur Science Research Institute Co Ltd
Priority date: 2016-06-21
Filing date: 2016-06-21
Publication date: 2017-01-04
Anticipated expiration: 2026-06-21

Abstract

This utility model provides a kind of CAM structure based on FPGA, compares the register module group of data message for storage including one；One for judging the comparator module group whether having data to be compared in register module group, the register module one_to_one corresponding of the comparator module in comparator module group and register module group is also connected, and data to be compared are inputted by the input port of comparator module group；Also include a writing module that will compare data write register module group；One selection module for mask register module group seeking scope；Two MUX modules, the information comparing data is write in register module by one of them MUX module and stores by writing module, the comparator module in comparator module group by the register module of the output of another MUX module and data match to be compared at the address signal of register module group.This utility model can compare input data and all data of Parasites Fauna parallel, improves search efficiency.

Description

A kind of CAM structure based on FPGA

Technical field

This utility model relates to data communication technology field, a kind of CAM structure based on FPGA.

Background technology

Along with the fast development of communication technology, in network, the transmission speed of packet is more and more higher, such as, lead at switch In territory, if using traditional software mode to carry out routeing or MAC table inquiry, speed is slow, it is impossible to ensure data and Time transmission.

CAM chip has the advantage of parallel search, and the time of inquiry is the most unrelated with the data comprised in CAM so that CAM It is widely used in a network.But in the project that some are medium and small, especially in the project of FPGA, if outside Cai Yonging The CAM chip put, the utilization rate of first CAM chip will not be the highest, and next adds cost.

Summary of the invention

Technical assignment of the present utility model is to solve the deficiencies in the prior art, it is provided that a kind of CAM structure based on FPGA.

This utility model solves its technical problem and be the technical scheme is that

A kind of CAM structure based on FPGA, including

One register module group comparing data message for storage, described register module group includes that at least two is posted Buffer module；

One for judging the comparator module group whether having data to be compared in register module group, comparator module group There is input port, comparator module group at least two comparator module, the comparator module in comparator module group with deposit The register module one_to_one corresponding of device module group is also connected, and data to be compared are carried out defeated by the input port of comparator module group Enter；

Also include

One will be compared the writing module of data write register module group；

One selection module for mask register module group seeking scope, selects module to be connected to comparator module Group, by the register module inputted in parallel comparand register module group of selection of configuration module, in comparator module group Comparator module output and the register module information of data match to be compared；

Two MUX modules, the information comparing data is write depositor mould by one of them MUX module by writing module Storing in block, the comparator module in comparator module group is by the output of another MUX module and data to be compared phase The register module joined is at the address signal of register module group.

Concrete, writing module includes writing enable, write address port and writing FPDP.

Concrete, register module group comprises even number register module, comparator module group comprises the most accordingly Even number comparator module, by the input of selection of configuration module, by equal for the register module being connected one by one with comparator module It is divided at least two parts, with parallel relatively with the register module of a part.

Preferably, register module group includes four register modules, and accordingly, comparator module group includes four comparators Module, is divided into two parts by the register module being connected one by one with comparator module, often by the input of selection of configuration module Part includes two register modules, with parallel relatively with two register modules of a part.

A kind of CAM structure based on FPGA of the present utility model compared with prior art produced by provide the benefit that:

This utility model is reasonable in design, simple in construction, can compare input data and all data of Parasites Fauna parallel, and Unrelated with the size of Parasites Fauna, improve search efficiency.

Accompanying drawing explanation

Accompanying drawing 1 is structure principle chart of the present utility model.

In figure, each label represents:

10, register module group, 20, comparator module group, 30, writing module, 40, select module,

50, a MUX module, the 60, the 2nd MUX module.

Detailed description of the invention

Below in conjunction with the accompanying drawings 1, as a example by the CAM structure figure of a 4x4, to of the present utility model a kind of based on FPGA CAM structure is described in detail below.

As shown in Figure 1, a kind of CAM structure based on FPGA of the present utility model, its structure includes

One register module group 10 comparing data message for storage, described register module group 10 includes at least two Individual register module；

One for judging the comparator module group 20 whether having data to be compared in register module group 10, comparator mould Block group 20 has input port, comparator module group 20 at least two comparator module, the comparator in comparator module group 20 The register module one_to_one corresponding of module and register module group 10 is also connected, and data to be compared are defeated by comparator module group 20 Inbound port inputs.

Described CAM structure also includes

One will be compared the writing module 30 of data write register module group 10；

One selection module 40 for mask register module group 10 seeking scope, described selection module 40 is connected to ratio Relatively device module group 20, by the register module inputted in parallel comparand register module group 10 of selection of configuration module 40, than The register module information with data match to be compared is exported compared with the comparator module in device module group 20；

Oneth MUX module 50 and the 2nd MUX module 60, writing module 30 will compare data by a MUX module 50 Storing in information write register module, the comparator module in comparator module group 20 is exported by the 2nd MUX module With the register module of data match to be compared at the address signal of register module group 10.

Writing module 30 includes writing enable, write address port and writing FPDP.

Register module group 10 includes four register modules, is called register module 1, register module 2, deposits Device module 3, register module 4；Accordingly, comparator module group 20 includes four comparator module, be respectively compared device module 1, Comparator module 2, comparator module 3, comparator module 4, by the input of selection of configuration module 40, by register module group 10 In four register modules be divided into two parts, i.e. register module 1 and register module 2 be a part, register module 3 It is a part with register module 4, with parallel comparand register module 1 and register module 2, or register module 3 and posting Buffer module 4.

Utility model works process:

1) write in CAM and compare data.First pass through the write address port of writing module 30 and write FPDP input wr_ Addr and wr_data, meanwhile, a MUX module 50 writes wr_data according to wr_addr to the register module specified.This mistake Journey is the write of CAM content.

2) the register module number compared parallel is specified.When sel signal is 1 in selection module 40, enable comparator Module 1 and comparator module 2, and comparator module 3 and comparator module 4 do not work, data the most to be compared are at depositor mould Parallel search in block 1 and register module 2.Otherwise, when sel signal is 0, data to be compared are at register module 3 and deposit Parallel search in device module 4.When register module number is many, select seeking scope can reduce structure power consumption.

3) output match signal.When in comparator module, the output result of any one is 1, match signal is just 1, Represent in CAM structure, find the data mated.

4) output match_addr signal.2nd MUX module 60 can be determined that according to the output of each comparator module The numerical value of which register module is equal with data to be compared, thus obtains OPADD.

Last it should be noted that above content is only in order to illustrate the technical solution of the utility model, rather than to this practicality The restriction of novel protected scope, although this utility model has been made to explain by this detailed description of the invention part, this area It is to be appreciated by one skilled in the art that the technical solution of the utility model can be modified or equivalent, without deviating from The spirit and scope of technical solutions of the utility model.

Claims

1. a CAM structure based on FPGA, it is characterised in that include

One register module group comparing data message for storage, described register module group includes at least two depositor Module；

One for judging the comparator module group whether having data to be compared in register module group, described comparator module group There is input port, comparator module group at least two comparator module, the comparator module in comparator module group with deposit The register module one_to_one corresponding of device module group is also connected, and described data to be compared are carried out by the input port of comparator module group Input；

Also include

One will be compared the writing module of data write register module group；

One selection module for mask register module group seeking scope, described selection module is connected to comparator module Group, by the register module inputted in parallel comparand register module group of selection of configuration module, in comparator module group Comparator module output and the register module information of data match to be compared；

Two MUX modules, the information comparing data is write in register module by writing module by one of them MUX module Storing, the comparator module in comparator module group is by the output of another MUX module and data match to be compared Register module is at the address signal of register module group.

A kind of CAM structure based on FPGA the most according to claim 1, it is characterised in that said write module includes writing Enable, write address port and write FPDP.

A kind of CAM structure based on FPGA the most according to claim 1, it is characterised in that in described register module group Comprise even number register module, described comparator module group comprises even number comparator module the most accordingly, by configuring Select the input of module, the register module being connected one by one with comparator module is divided at least two parts, to compare parallel Register module with a part.

A kind of CAM structure based on FPGA the most according to claim 3, it is characterised in that described register module group bag Including four register modules, described comparator module group includes four comparator module, will by the input of selection of configuration module The register module being connected one by one with comparator module is divided into two parts, and every part includes two register modules, with parallel Relatively with two register modules of a part.