Week - 09           Embedded Programming

 

 

All MCs use one of two basic design models:

Harvard Architecture and von-Neumann architecture.

• They represent two different ways of exchanging data between CPU and Memory

 

 

 

Memory

 

In present days, the audio & video is totally digitized. When the audio signal is out of any audio source or microphone, then the analog will be sampled, coded, modulated, compressed & processed into the digital form like zero’s and one’s, so it is named as DSP (Digital Signal Processing). The remaking of digital signal into audio signal is done by the digital signal processing. The architecture of traditional X86 is called “Von Neumann”, and it is not suitable for handling several algorithms to route this type of digital data. The most popular “Harvard Architecture” is used to handle complex DSP algorithms, and this algorithm is used in most popular and advanced RISC machine processors. Here, in this article we have discussed about Von Nevuman architecture and Harward architecture.

 Von Neuman Architecture A Von Neuman architecture is nothing but it is an art that how an electronic computer can be stored. This is not a new concept at all and for a long time it has been there and we are following the principle of this Von Neuman architecture. If we will go back in history, it is quite evident that the Von Neuman architecture was first published in John von Neumann’s report in June 30, 1945 and since then the same principle is being implemented for the storing of electronic computers. Application and Features of the Von Neuman Architecture The Von Neuman architecture has got extensive application in everyday life. Keeping in mind the extensive application the Von Neuman architecture has been introduced as a subject in the engendering degree. From the third semester engineering students will have the subject as their curriculum. The Von Neuman architecture consists of some important features and here we will have a detailed elaboration to the features. Memory: We all know that the Von Neuman is nothing but a computer having the feature of data storage. In the architecture of the Von Neuman the memory plays a vital role and it is considered as one of the important feature. Mainly this is responsible for both holding and starting of data and programming data. In modern days this has been replaced by the RAM and now we are using RAM for this purpose. Control Unit: This unit is mainly responsible for the controlling aspect. All the data stored in the memory and during the processing of data the control unit plays the role and it manages the data flow. In fact, to be more typically it is “One At A Time”. The control unit follows the principle of the One At A Time and accordingly it process all the data. Input– output: Like all electronics devices the Von Neuman architecture also has an input/output architecture. It is the basic function is same and nothing specially has been designed for the input and output architecture. With the Input and output device on a person can communicate with the device. ALU: ALU or the Arithmetic Logic Unit has a great importance in the Von Neuman architecture. Any sort of addition, subtraction, multiplication and division of the data will be carried out by this ALU. In addition to that any other kind of algorithmic function and activities will be carried out by the ALU. These are the basic aspect of the Von Neuman architecture which you must aware of.

Harvard Architecture :

 

The Harvard architecture is nothing but a kind of storage of data. When it comes to the physical storage of the data the Harvard architecture always stood first. Though the concept is a not a new one still the Harvard architecture has got huge appreciation form all. The Harvard Mark I relay-based computer is the term from where the concept of the Harvard architecture first arises and then onwards there has been a significant development with this architecture. The main function of this architecture is to separate and physical storage of the data and giving the signal pathways for instruction and data.

Application and Features of the Harvard Architecture It has got an extensive application in the audio and video processing products and with every audio and video processing instrument you will notice the presence of Havard architecture. Black-fin processors by Analog Devices, Inc. is the particular device where it has got a premier use. In other electronic chip based product the Havard architecture is also widely used. Memory Status In the previous architecture, we have witnessed the presence of two memories. However, in case of the Harvard architecture you will not find two memory and there will be one memory. The existing memory will be able to perform all the functions. Yes, there will be only read only memory and this memory will be used for the purpose of reading, coding, decoding and storing of data. The speed aspect A lot has been discussed about the Harvard architecture, but without the speed any architecture can’t be accepted. But in case of the Havard architecture the manufacturers have designed the architecture in such a way that it will be able to process the data with a much higher speed. Yes, all care has been taken so that the architecture can process data with a high speed. By implementing the same formula the modern days CPU are being manufactured so that the new CPU can run with a much faster sped and can also process the data effectively. The concept of the CPU cache is also being implemented while designing the Harvard architecture. Why Harvard Architecture is Effective? After coming across all, the fact definitely one question will strike to your mind that why Harvard architecture is so effective. The answer is quite clear and simple that the architecture is able to read an instruction and it can also perform data memory access simultaneously at a fast speed. Hence the Harvard architecture is being widely accepted. Difference between Von Neuman and Harvard Architecture The features and the specifications of both the architectures are discussed and the basic function of both architectures is to design the computer architecture. However, in certain aspects, both the architectures differ from one another and here we will elaborate the basic difference between the Von Neuman and Harvard Architecture. Whenever you are watching a video it is synchronized between the audio and the video. If the audio microphone or chip goes out of control you can’t enjoy the video and vice versa, and the same concept is applicable here also. The Von Neuman is a kind of architecture which is more prominently seen in the case of the conventional processor and in today also the same principle is being implemented. PCs and Servers, and embedded systems are coming under the conventional and the traditional processors which run only with control function and here you will notice the Van Neuman architecture. On the contrast the Havard architecture is seen in the case of the modern and the latest processors like DSPs and other processors. In addition to the above Mobile communication systems, audio, speech and image processing systems are the place where you will find the application of the Havard architecture. In Von Neuman both the data and the programs are ignored in same memory, but in the later case separate memory is used for the above purpose. Hence, in the storing the data aspect both differs from each other.

 

Coding also differ in both the architecture. The Von Neuman is a kind of architecture where you will find that the codes are executed serially and takes more clock cycles, whereas in case of the later the same does not happen. The Havard architecture follows a parallel level of coding.

 

You will not find excessive number of multiplier in the case of the Von Neuman architecture, but in case of the Havard architecture you will find a large number of the multiplier. In addition to that, both architectures differ from each other in various aspects like presence of barrel shifter, optimization of programming, processing speed and lot more.

 

Thus, this is all about Onevuman architecture and Harward architecture with applications and features. We hope that you have got a better understanding of this concept, furthermore, any queries regarding this concept, or micro-controller based electronic projects please give your feedback by commenting in the comment section below. Here is a question for you, which architecture is so effective?