Mobile Operating Systems Lesson 03 PalmOS Part 1 Oxford University Press 2007. All rights reserved. 1
PalmOS An OS for handheld devices Designed for highly efficient running of small productivity programs for devices with a few application tasks Offers high performance due to a special feature that it supports only one process which controls all computations by the event handlers Oxford University Press 2007. All rights reserved. 2
PalmOS Features Single process (no multi-processing and multi-threading) Compiled for a specific set of hardware, performance very finely tuned Memory space partitioned into program memory and multiple storage heaps for data and applications Oxford University Press 2007. All rights reserved. 3
PalmOS Features A file in format of a database IP-based network connectivity and WiFi (in later version only) Integration to cellular GSM/CDMA phone Oxford University Press 2007. All rights reserved. 4
PalmOS No multi-processing or multi-tasking Simplifies the kernel of the OS there is an infinite waiting loop in the only process that kernel runs The loop polls for an event Oxford University Press 2007. All rights reserved. 5
Polling for events at specific intervals Each polled event sends interrupt signal Handled by an event handler Functioning as non-maskable nonprioritized ISR Oxford University Press 2007. All rights reserved. 6
Example: Polling for the events For a request to run an application or sub-application For a search program request to process a query Notifications (like time-out alarm) GUI actions (such as touching or tapping the screen with stylus) Oxford University Press 2007. All rights reserved. 7
PalmOS Hardware Support Compiles for a specific set of hardware, its performance is very finely tuned Optimized to support a very specific range of hardware, CPU, controller chips, and smaller screens of Palm OSbased devices Oxford University Press 2007. All rights reserved. 8
Display Screen Support Generally wide screen 160 160 pixels Optimized layout of desktop programs displayed on screen 256 colour touch screen Higher resolution support in new versions Oxford University Press 2007. All rights reserved. 9
PalmOS Memory Support 16 MB memory 256 MB internal flash (non-volatile ROM) 256 MB card consisting of flash memory which the user inserts into the device Oxford University Press 2007. All rights reserved. 10
PalmOS Memory Space Partitions Program memory dynamic heap for process stacks and global variables Multiple storage heaps for data and applications Oxford University Press 2007. All rights reserved. 11
PalmOS File Format Format of a database Multiple records Information fields about the file name, attributes, and version of the database for the application Oxford University Press 2007. All rights reserved. 12
PalmOS Connectivity IP-based network connectivity WiFi (in later version only) Wireless communication protocols Integration to cellular GSM/CDMA phone Oxford University Press 2007. All rights reserved. 13
PalmOS APIs Simple APIs compared to Windows CE Simple APIs for developing the GUIs buttons, menus, scroll bar, dialogs, forms, and tables Using HTML markup language Oxford University Press 2007. All rights reserved. 14
PalmOS Desktop and Desktop Programs Desktop for Windows and Mac both and other essential software SMS, Address, Card-Info, HotSync, To- Do-List, SMS, Security, Date Book/Calendar, Calc, Welcome, and Clock Oxford University Press 2007. All rights reserved. 15
PalmOS PIM Address book Data book for task-to-do and organization Memo pad SMTP (simple mail transfer protocol) email download Oxford University Press 2007. All rights reserved. 16
PalmOS PIM Offline creation and sending of POP3 (post office protocol 3) email Internet browsing functions using Blazer (a browser for handhelds) Windows organizer PDA (personal digital assistant) Oxford University Press 2007. All rights reserved. 17
PalmOS Query Development Platform Query development support platform Palm query applications (PQA) written using HTML and ported at Palm device Oxford University Press 2007. All rights reserved. 18
PalmOS Client side Applications GUI development support on C/C++ platform using Palm SDK For Java application using J2ME and advanced tools, for example, Metrowerk CodeWarrior Multimedia applications such as playing music (Palm Tungsten) Oxford University Press 2007. All rights reserved. 19
PalmOS Ports Serial and infrared ports for communication with mobile phones and external modems Synchroniszing a PC personal area computer using HotSync after resolving the conflicts in different versions of files during data exchange Oxford University Press 2007. All rights reserved. 20
Port Protocols IrDA or serial device System mounted on a cradle Connects to computerpcs through IR or serial port A cradle is an attachment on which the handheld device can rest near a PC and connects to the PC via a USB or infrared Oxford University Press 2007. All rights reserved. 21
Device handling Assumed as a new flash drive of a PC HotSync facilitates drag and drop of files from device to PC and vice versa Oxford University Press 2007. All rights reserved. 22
Cards MMC (multimedia card) SD (secure digital) memory card SDIO (secure digital input/output) memory card Oxford University Press 2007. All rights reserved. 23
Third Party applications support Examples games Travel and flight planner Calculator Graphic drawings Preparing slide shows Oxford University Press 2007. All rights reserved. 24
Application layer in architectural layers of PalmOS Oxford University Press 2007. All rights reserved. 25
OS and hardware layer in architectural layers of PalmOS Oxford University Press 2007. All rights reserved. 26
Lowest level layer in OS Kernel Directly interfaces the assembler, firmware (software installed in the hardware devices in the system), and hardware PalmOS has a micro-kernel Oxford University Press 2007. All rights reserved. 27
PalmOS 4.x Adds improved security Improved GUIs,VUIs, telephony libraries Standard interfaces for access to the external SD cards for the files Oxford University Press 2007. All rights reserved. 28
PalmOS 5.x Supports (i) a standardized API for high resolution screen (ii) dynamic input areas Oxford University Press 2007. All rights reserved. 29
PalmOS 5.x (iii) instead of persistent battery-backed RAM, a non-volatile file system using flash memory saves the files and data in case the battery charge is draining out (iv) ARM, the processor providing efficient code and an energy-efficient architecture Oxford University Press 2007. All rights reserved. 30
Advanced PalmOS Handheld Merged PDA and smart phones Feature to double as a hard drive using USB cable to PC Enables the drag and drop of files between the Palm and PC in a manner similar to the drag and drop functions in a PC between C: and D: drives Oxford University Press 2007. All rights reserved. 31
Recent Developments Integration in Wndows CE A few Windows mobile handheld devices in use are Palm look-alikes But these do not deploy PalmOS platform but Windows CE Oxford University Press 2007. All rights reserved. 32
PalmOS Deficiencies 1. Instead of multi-tasking, PalmOS provides for running a sub-application from within an application Oxford University Press 2007. All rights reserved. 33
PalmOS Deficiencies 2. Not an ideal platform for running multimedia applications because due to PalmOS is not for designing real-time systems Oxford University Press 2007. All rights reserved. 34
PalmOS Deficiencies 3. Does not offer much expandability 4. Inability to adapt to different sorts of hardware may also be considered a limitation for this operating system Oxford University Press 2007. All rights reserved. 35
Summary PalmOS designed for highly efficient running of small productivity programs for devices with a few application tasks No multiprocessing support Simple File record as database HotSync Integrates with phone, Internet, and WiFi Oxford University Press 2007. All rights reserved. 36
End of Lesson 03 PalmOS Part 1 Oxford University Press 2007. All rights reserved. 37