Trends in Embedded Systems

TRENDS IN EMBEDDED SYSTEMS

Chapter Structure

Objectives

1 Introduction

2 Processor Trends

3 Operating System Trends

4 Development Language Trends

5 Open Standards, Frameworks and alliances

6 Bottlenecks faced by Embedded Industry

OBJECTIVES

After reading this chapter you will understand:

Different trends in the embedded industry related to:

Processor Trends

Operating System Trends

Development Language Trends

Open Standards, Frameworks and alliances

Bottlenecks faced by Embedded Industry

1 INTRODUCTION

This concluding chapter describes the trends in the embedded systems industry.

2 PROCESSOR TRENDS

There have been tremendous advancements in the area of processor design.

Following are some of the points of difference between the first generation of processor/controller and today’s processor/ controller.

Number of ICs per chip: Early processors had a few number of IC/gates per chip. Today’s processors with Very Large Scale Integration (VLSI) technology can pack together ten of thousands of IC/gates per processor.

Need for individual components: Early processors need different components like brown out circuit, timers, DAC/ADC separately interfaced if required to be used in the circuit. Today’s processors have all these components on the same chip as the processor.

Speed of Execution: Early processors were slow in terms of number of instructions executed per second. Today’s processor with advanced architecture support features like instruction pipeline improving the execution speed.

Clock frequency: Early processors could execute at a frequency of a few MHz only. Today’s processors are capable of achieving execution frequency in rage of GHz.

O Application specific processor: Early systems were designed using the processors available at that time. Today it is possible to custom create a processor according to a product requirement.

Following are the major trends in processor architecture in embedded development.

System on Chip (SoC)

This concept makes it possible to integrate almost all functional systems required to build an embedded product into a single chip.

SoC are now available for a wide variety of diverse applications like Set Top boxes, Media Players, PDA, etc.

SoC integrate multiple functional components on the same chip thereby saving board space which helps to miniaturize the overall design.

Multicore Processors/ Chiplevel Multi Processor

This concept employs multiple cores on the same processor chip operating at the same clock frequency and battery.

Based on the number of cores, these processors are known as:

o  Dual Core – 2 cores

o   Tri Core – 3 cores

Quad Core – 4 cores

These processors implement multiprocessing concept where each core implements pipelining and multithreading.

Reconfigurable Processors

It is a processor with reconfigurable hardware features.

Depending on the requirement, reconfigurable processors can change their functionality to adapt to the new requirement. Example: A reconfigurable processor chip can be configured as the heart of a camera or that of media player.

These processors contain an Array of Programming Elements (PE) along with a microprocessor. The PE can be used as a computational engine like ALU or a memory element.

3 OPERATING SYSTEM TRENDS

The advancements in processor technology have caused a major change in the Embedded Operating System Industry.

There are lots of options for embedded operating system to select from which can be both commercial and proprietary or Open Source.

Virtualization concept is brought in picture in the embedded OS industry which replaces the monolithic architecture with the microkernel architecture.

This enables only essential services to be contained in the kernel and the rest are installed as services in the user space as is done in Mobile phones.

Off the shelf OS customized for specific device requirements are now becoming a major trend.

4 DEVELOPMENT LANGUAGE TRENDS

There are two aspects to Development Languages with respect to Embedded Systems Development

Embedded Firmware

It is the application that is responsible for execution of embedded system.

It is the software that performs low level hardware interaction, memory management etc on the embedded system.

Embedded Software

It is the software that runs on the host computer and is responsible for interfacing with the embedded system.

It is the user application that executes on top of the embedded system on a host computer.

Early languages available for embedded systems development were limited to C & C++ only. Now languages like Microsoft C$, ASP.NET, VB, Java, etc are available.

Java

Java is not a popular language for embedded systems development due to its nature of execution.

Java programs are compiled by a compiler into bytecode. This bytecode is then converted by the JVM into processor specific object code.

During runtime, this interpretation of the bytecode by the JVM makes java applications slower that other cross compiled applications.

This disadvantage is overcome by providing in built hardware support for java bytecode execution.

Another technique used to speed up execution of java bytecode is using Just In Time (JIT) compiler. It speeds up the program execution by caching all previously executed instruction.

Following are some of the disadvantage of Java in Embedded Systems development:

o For real time applications java is slow

Garbage collector of Java is non-deterministic in behavior which makes it not suitable for hard real time systems.

o Processors need to have a built in version of JVM

Those processors that don’t have JVM require it to be ported for the specific processor architecture.

Java is limited in terms of low level hardware handling compared to C and C++

Runtime memory requirement of JAVA is high which is not affordable by embedded systems.

B. .NET CF

It stands for .NET Compact Framework.

.NET CF is a replacement of the original .NET framework to be used on embedded systems.

The CF version is customized to contain all the necessary components for application development.

The Original version of .NET Framework is very large and hence not a good choice for embedded development.

The .NET Framework is a collection of precompiled libraries.

Common Language Runtime (CLR) is the runtime environment of .NET. It provides functions like memory management, exception handling, etc.

Applications written in .NET are compiled to a platform neutral language called Common Intermediate Language (CIL).

For execution, the CIL is converted to target specific machine instructions by CLR.

5 OPEN  STANDARDS,  FRAMEWORKS  AND ALLIANCES

 Standards are necessary for ensuring interoperability. With diverse market it is essential to have formal specifications to ensure interoperability.

Following are some of the popular strategic alliances, open source standards and frameworks specific to the mobile handset industry.

Open Mobile Alliance (OMA)

It is a standard body for creating open standards for mobile industry.

OMA is the Leading Industry Forum for Developing Market Driven – Interoperable Mobile Service Enablers

OMA was formed in June 2002 by the world’s leading mobile operators, device and network suppliers, information technology companies and content and service providers.

OMA delivers open specifications for creating interoperable services that work across all geographical boundaries, on any bearer network. OMA’s specifications support the billions of new and existing fixed and mobile terminals across a variety of mobile networks, including traditional cellular operator networks and emerging networks supporting machine-to-machine device communication.

OMA is the focal point for the development of mobile service enabler specifications, which support the creation of interoperable end-to-end mobile services.

Goals of OMA

Deliver high quality, open technical specifications based upon market requirements that drive modularity, extensibility, and consistency amongst enablers to reduce industry implementation efforts.

Ensure OMA service enabler specifications provide interoperability across different devices, geographies, service providers, operators, and networks; facilitate interoperability of the resulting product implementations.

 Be the catalyst for the consolidation of standards activity within the mobile data service industry; working in conjunction with other existing standards organizations and industry fora to improve interoperability and decrease operational costs for all involved.

Provide value and benefits to members in OMA from all parts of the value chain including content and service

providers, information technology providers, mobile operators and wireless vendors such that they elect to actively participate in the organization.

Open Handset Alliance (OHA)

The Open Handset Alliance is a group of 84 technology and mobile companies who have come together to accelerate innovation in mobile and offer consumers a richer, less expensive, and better mobile experience. Together they have developed Android™, the first complete, open, and free mobile platform and are committed to commercially deploy handsets and services using the Android Platform.

Members of OHA include mobile operators, handset manufacturers, semiconductor companies, software companies, and commercialization companies.

Android

Android is an operating system based on the Linux kernel, and designed primarily for touchscreen mobile devices such as smartphones and tablet computers.

Initially developed by Android, Inc., which Google supported financially and later bought in 2005, Android was unveiled in 2007 along with the founding of the Open Handset Alliance: a consortium of hardware, software, and telecommunication companies devoted to advancing open standards for mobile devices.

The first publicly-available Smartphone to run Android, the  HTC Dream, was released on October 18, 2008

Openmoko

Openmoko is a project to create a family of open source mobile phones, including the hardware specification and the operating system.

The first sub-project is Openmoko Linux, a Linux-based operating system designed for mobile phones, built using free software.

The second sub-project is developing hardware devices on which Openmoko Linux runs.

6 Bottlenecks faced by Embedded Industry

Following are some of the problems faced by the embedded devices industry:

Memory Performance

The rate at which processors can process may have increased considerably but rate at which memory speed is increasing is slower.

Lack of Standards/ Conformance to standards

Standards in the embedded industry are followed only in certain handful areas like Mobile handsets.

There is growing trend of proprietary architecture and design in other areas.

Lack of Skilled Resource

Most important aspect in the development of embedded system is availability of skilled labor. There may be thousands of developers who know how to code in C, C++, Java or .NET but very few in embedded software.