12-04-2011, 04:06 PM
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INTRODUCTION
Just like PCs have an operating system like Windows, Symbian is the O.S for mobile phones. But unlike PC design, mobile phone put constrains on a suitable O.S. The operating system has to have a low memory footprint, and low dynamic memory usage, and efficient power management framework and real time support for communication and telephony protocols. Symbian OS is designed for the mobile phone environment .It addresses constraints of mobile phones by providing a framework to handle low memory situations, a power management., and a rich software layer implementing industry standards for communication , telephony and data rendering .
Symbian OS is designed for the specific requirements of open, advanced , data enabled 2G , 3G mobile phones . Compact enough to fit in the memory of a mobile phone, Symbian OS was planned from the beginning to be a full operating system in terms of functionality. Symbian OS is already available in Ericsson R380 smart phones, Nokia 9200 communicator series, the Nokia 7650 and Sony Ericsson P800
Key features of Symbian OS are:
• Rich suit of application engines – Including contacts, schedules, messaging, browsing, office, utility and system control
• Browsing – fit for the purpose of browsing engine, for full web browser support and WAP stack for mobile browsing
• Messaging – multimedia messaging using MMS, picture messaging with EMS and text messaging using SMS
• Multimedia – shared access to screen, keyboards, phones and bitmaps; audio recording and play back, and image related to functionality (support for all common audio and image format)
• Communication protocol – wide area networking stacks including TCP, IP version 4 , IP version 6 and personal area networking stacks including Blue tooth , and USB.
• Software development – 3 main programming and content development options: C++, Java, WAP.
EVOLUTION
Symbian OS development was a joint venture of world’s leading mobile phone companies like Nokia , Ericsson and Motorola . After the introduction of first generation mobile phones, these companies realized that adding new functionalities to their handsets was a key market sector. Thus back in 1998, they jointly developed an operating system suited for mobile phone environment.
The first open Symbian OS phones are the Sony ericsson’s P800 smartphones, the Nokia 9200 series and the Nokia 7650 . Today two versions, Symbian OS v7 and v6 has evolved and extensively used . With improved picture resolution and flexible user interfaces, today’s mobile phones are capable of replacing PDAs and even the Palmtops.
HARDWARE
Mobile phone hardware can be divided in to three logic layers:
1. The CPU core.
2. The system on chip (SoC).
3. The phone PCB.
Figure 1: Mobile phone hardware can be divided into three logical layers: The CPU core, the SoC and the PCB. Symbian OS also conforms to this layering. This enables easy porting of Symbian OS as the code for particular CPU core or SoC can be reused in many products
CPU CORE
Central to data enabled mobile phones is a fast, low power, low cost CPU core, which has a compact code and can be highly integrated with peripherals .The family of ARM architecture RISC processors are usually used .The CPU core has a memory management unit (MMU) for efficient usage of valuable memory space, and a cache for speedy access of data. The CPU core must be capable of operating in various privileged access modes to handle interrupts and exceptions .It is here, all the logic calculations and decisions are being carried out.
SYSTEM ON CHIP (SoC)
The CPU core is placed in an SoC . SoC also contains timers, interrupt controllers, DMA controllers and other vital peripherals for the effective functioning of phone operating system.These SoCs are often commercially available and are some times custom build by handset manufacturers . Some of the SoCs developed by Intel are Intel strong ARM processor series and Intel X-scale series.
PHONE PCB
Phone PCB is the motherboard of mobile. The system on chip (SoC) is placed in the phone PCB. The I\O systems like LCD , keypad , audio codec , radio , etc. are connected to this PCB. It also contains some memory.
MEMORY MANAGEMENT UNIT (MMU)
MMU is a hardware unit which performs the task of converting linear addresses, as they appear as outputs from a program, into physical addresses that access a physical memory location placed anywhere within the memory system. MMU has a memory paging mechanism, which allows much physical memory location to be assigned to any linear address. The linear address is defined as the address generated by a program. With a memory paging unit, the linear address is invisibly translated into any physical address, which allows an application written to function at a specific address to be relocated through paging mechanism.
MMU also protects process data from access by other processes, enforces protection of application and kernel codes and isolates the hardware from the application codes. The MMU is a crucial component in the design of the protected mode system , which enhances both the security and stability of the platform. A standard two-level page tabled MMU allows small 4 KB pages for efficient memory usage.
INTRODUCTION
Just like PCs have an operating system like Windows, Symbian is the O.S for mobile phones. But unlike PC design, mobile phone put constrains on a suitable O.S. The operating system has to have a low memory footprint, and low dynamic memory usage, and efficient power management framework and real time support for communication and telephony protocols. Symbian OS is designed for the mobile phone environment .It addresses constraints of mobile phones by providing a framework to handle low memory situations, a power management., and a rich software layer implementing industry standards for communication , telephony and data rendering .
Symbian OS is designed for the specific requirements of open, advanced , data enabled 2G , 3G mobile phones . Compact enough to fit in the memory of a mobile phone, Symbian OS was planned from the beginning to be a full operating system in terms of functionality. Symbian OS is already available in Ericsson R380 smart phones, Nokia 9200 communicator series, the Nokia 7650 and Sony Ericsson P800
Key features of Symbian OS are:
• Rich suit of application engines – Including contacts, schedules, messaging, browsing, office, utility and system control
• Browsing – fit for the purpose of browsing engine, for full web browser support and WAP stack for mobile browsing
• Messaging – multimedia messaging using MMS, picture messaging with EMS and text messaging using SMS
• Multimedia – shared access to screen, keyboards, phones and bitmaps; audio recording and play back, and image related to functionality (support for all common audio and image format)
• Communication protocol – wide area networking stacks including TCP, IP version 4 , IP version 6 and personal area networking stacks including Blue tooth , and USB.
• Software development – 3 main programming and content development options: C++, Java, WAP.
EVOLUTION
Symbian OS development was a joint venture of world’s leading mobile phone companies like Nokia , Ericsson and Motorola . After the introduction of first generation mobile phones, these companies realized that adding new functionalities to their handsets was a key market sector. Thus back in 1998, they jointly developed an operating system suited for mobile phone environment.
The first open Symbian OS phones are the Sony ericsson’s P800 smartphones, the Nokia 9200 series and the Nokia 7650 . Today two versions, Symbian OS v7 and v6 has evolved and extensively used . With improved picture resolution and flexible user interfaces, today’s mobile phones are capable of replacing PDAs and even the Palmtops.
HARDWARE
Mobile phone hardware can be divided in to three logic layers:
1. The CPU core.
2. The system on chip (SoC).
3. The phone PCB.
Figure 1: Mobile phone hardware can be divided into three logical layers: The CPU core, the SoC and the PCB. Symbian OS also conforms to this layering. This enables easy porting of Symbian OS as the code for particular CPU core or SoC can be reused in many products
CPU CORE
Central to data enabled mobile phones is a fast, low power, low cost CPU core, which has a compact code and can be highly integrated with peripherals .The family of ARM architecture RISC processors are usually used .The CPU core has a memory management unit (MMU) for efficient usage of valuable memory space, and a cache for speedy access of data. The CPU core must be capable of operating in various privileged access modes to handle interrupts and exceptions .It is here, all the logic calculations and decisions are being carried out.
SYSTEM ON CHIP (SoC)
The CPU core is placed in an SoC . SoC also contains timers, interrupt controllers, DMA controllers and other vital peripherals for the effective functioning of phone operating system.These SoCs are often commercially available and are some times custom build by handset manufacturers . Some of the SoCs developed by Intel are Intel strong ARM processor series and Intel X-scale series.
PHONE PCB
Phone PCB is the motherboard of mobile. The system on chip (SoC) is placed in the phone PCB. The I\O systems like LCD , keypad , audio codec , radio , etc. are connected to this PCB. It also contains some memory.
MEMORY MANAGEMENT UNIT (MMU)
MMU is a hardware unit which performs the task of converting linear addresses, as they appear as outputs from a program, into physical addresses that access a physical memory location placed anywhere within the memory system. MMU has a memory paging mechanism, which allows much physical memory location to be assigned to any linear address. The linear address is defined as the address generated by a program. With a memory paging unit, the linear address is invisibly translated into any physical address, which allows an application written to function at a specific address to be relocated through paging mechanism.
MMU also protects process data from access by other processes, enforces protection of application and kernel codes and isolates the hardware from the application codes. The MMU is a crucial component in the design of the protected mode system , which enhances both the security and stability of the platform. A standard two-level page tabled MMU allows small 4 KB pages for efficient memory usage.
