SoftCore Processors

A softcore processor in its simplest sense can be defined as a HDL(Verilog/Vhdl) code with which an FPGA can be programmed so that it behaves like a processor.That is ,it enables us to built a processor system which we can configure ourselves inorder to optimize the perfomance to meet our requirements.
The most successful of the commercial processors like ARM have distinguished themselves in being suited to a large no.of different purposes as well as being cost effective.The ability to achieve real time operation also remains as its trademark.The softcore processsor on the other hand is unique for its reconfigurability.It can we configured as a fast system for achieving real time operations as well as a small system in case of size constrained projects.Various embedded peripherals like timers, uart blocks,dma blocks SDRAM memories are also available along with the processor in softcore form so that we can choose among the available components ,those we require to built our own custominzed processor system.The design can be modified at will any time.
The design of a softcore processor system can be done in very short time using the CAD software provide by the various FPGA vendors. We just have to pick the required configuration of the processor as well as choose the associated components.The software will generate the code for the components.But the best part is that the interfacing logic between various components also is generated by the tool.This saves much of our time as don't have to worry about interfacing between different components which may be different in bit length,speed,memory etc.Once the system design is finished we can straight away burn the code to our FPGA using the same tool and then test the system.we can run the our code working code on the system by making a little variations that make it compatible with the components used.The processor system provides a function rich API for accessing the components in our system and we can use them easily to modify our code.So no extra effort is needed to learn any new language or so...
The most popular softcore processors available in the market are microblaze from Xilinx and Nios II from Altera.For more information checkout these links

http://www.xilinx.com/xlnx/xebiz/designResources/ip_product_details.jsp?key=micro_blaze

http://www.altera.com/products/software/products/nios2/emb-nios2_ide.html

FPGAs -The new age

FPGAs (for Field programmable gate array) have been involved in the development of all most all new age products.Their popularity has now touched every section of the market thanks to their reconfigurability and low cost perfomance.Lets see how they came into existance at the first place..

FPGAs became popular in the 1980s.Till then most of the embedded processing was carried out using microprocessors or microcontrollers with their assosiated components.But the main problem pertaining to their use was the 'glue logic' which namely refers to the interface between two datasystems having different interfaces.Inorder to make communication possible between such systems based on different protocols some component was needed which at that time was satisfied by using custom logic ICs .These ICs were designed for meeting specific customer requirements and due to that reason the idea of making a general purpose IC was almost out of the question.Also the cost involved when fabricating these MSI ICs was enormous making them a rather cumbersome solution.This is where the idea of reconfigurable logic took form..FPGAs were an effiecient substitute for these glue logic ICs mailny because of two reasons..First is that they were reconfigurable so that effiecient designing and optimization could take place at every level.The component could be redesigned at will until it met all the project requirements and could even be redesigned if the design needed to be modified later.Secondly the designing and the eventual generation of the custom component could be done by the personnel using PC assosiated CAD software as opposed to the IC designing process which involved a large no of steps starting from designing to implementation as well as the expertise of several men.Thus emerged the FPGAs ;with a view to the future and still remains as one of the most preffered technologies .The market is on the rise and it hopes to remain so for the coming years as well