1. T-Engine Middleware Tomas Sanchez Lopez Real-time & Embedded Systems Laboratory tomas@icu.ac.kr

2. A N T S 2Contents Introduction Middleware Classification Middleware Activities T-Format Device Drivers Subsystems T-Collection T-Builder T-Dist Conclusions

3. A N T S 3Introduction T-Engine open standardreal-time T-Engine : An open standard platform for real-time, embedded systems development Middleware software agents intermediary Middleware : software agents acting as an intermediary between different application components

4. A N T S 4Introduction T-Engine Middleware: T-KernelT-Format T-Engine Middleware: Layer that provides services to application software with user-defined system calls, application tasks, and libraries offered by T-Kernel. The T-Format specification standardizes formats for middleware source and execution code.

5. A N T S 5 Middleware Classification A A - By the way it acts Subsystem-type Middleware Device Driver-type Middleware Library-type Middleware User Task-type Middleware B B - By the service it provides Device Driver-type Middleware Abstract Device Driver-type Middleware Extended Kernel-type Middleware Middleware to provide general functions

6. A N T S 6 Middleware Classification - A Subsystem-type Middleware Middleware which acts as a subsystems on the T-Kernel Called by the applications through its interface Called when event happens Device Driver-type Middleware Uses the device management functionality provided by the T-Kernel Use it through general device driver interface provided by T- Kernel More

7. A N T S 7 Middleware Classification - A Library-type Middleware Middleware that acts as a user library User apps need to be linked with it in code creation Provided function or global variable User Task-type Middleware Middleware that acts as a user-task server Management server Task User apps get services from it: Inter-task communication provided by T-Kernel Synchronization provided by T-Kernel

8. A N T S 8 Middleware Classification - B Device Driver-type Middleware Middleware that provides an API in a certain level of abstraction concerning: Each device on T-Engine Each device connected to T-engine Communication devices connect other devices To achieve portability, the API of lower level devices should be standardized Examples: RS232C driver, PCMCIA driver, Ethernet Driver, USB driver, Graphic Card Driver…

9. A N T S 9 Middleware Classification - B Abstract Device-type Middleware Provides SW interface of high abstraction to single or plural devices on T-Engine Extended Kernel-type Middleware Middleware that provides service or higher abstraction level through T-Kernel or middleware functions to HW and SW resources managed by T-Kernel Examples: TCP/IP, Printing I/F, FAT file system, GUI package… Examples: Process Management function, virtual memory function, loader function, CLI (command line interpreter)…

10. A N T S 10 Middleware Classification - B Middleware to provide General Functions Provides general calculation functions Weak relation with kernel resources or external devices Examples: Sort function, Search function, random number generation function, encryption/authentication function…

11. A N T S 11 Middleware Activities Related to the development of Middleware Standards T-Format Device Driver Specification Related to increasing amount of middleware Subsystem design Porting activities T-collection T-Builder Related to distribution of middleware T-Dist

12. A N T S 12 Middleware Stnd. ~ T-Format Code format of Middleware and application Software running on T-engine/T-Kernel. Source code style guidelines Source-code style format for middleware and applications running on T-Engine/T-kernel Source code written by various vendors can be compiled in one program Document format Type and format of documentation attached and distributed with middleware and applications

13. A N T S 13 Middleware Stnd. ~ T-Format Binary-code format Executable binary format to run in T-Engine/T-kernel Follow the ELF format Compiler dependent part of the ELF format should follow the GNU-based reference environment and is separately defined by T-Engine forum Symbol rules for avoiding name conflicts when combining different pieces of software from different vendors Global symbols (Exported functions, global variables, etc) Middleware Package name Version assignation Example: char unl_mpeg2_etronid[16];

14. A N T S 14 Middleware Stnd. ~ Device Driver Specifications of the Device Driver Interface Library Convenient dev. of device drivers designed to run on T-Kernel Device Drivers consist of: Interface layer Logical Layer Physical Layer Interface layer: Reduce burden on developers and bring together the aspects that can be standardized SDI (Simple Device driver interface layer) Devices that can perform all processing immediately without queuing requests (i.e. RTC or other register-based devices) GDI (General Device driver interface layer) For devices that must attend request in order of request (specially for those to interrupt processing) (i.e. RS-232C)

15. A N T S 15 Middleware Stnd. ~ Device Driver SDIGDI Also concerns about implementation issues: Waiting functions Abort functions Buffer management between the OS and the requesting source DMA Interrupt handlers

16. A N T S 16 Middleware Stnd. ~ Device Driver Examples Audio Device Driver Enables audio IO with T- Engine Provides audio codec control Allows extensions with more driver units and subunits (i.e. multiple implementations of ADC & DAC)

17. A N T S 17 Middleware Stnd. ~ Device Driver MIDI Device Driver T-Engine Units lack of MIDI connector Control the protocol converters and sending or receiving logical MIDI streams Individual devices are controlled by applications messages (not the MIDI driver) Back to Classification Examples

18. A N T S 18 Increasing Middle. ~ Subsystems T-Kernel doesnt include file management, GUI-related, communication functions, etc Implement these functionalities by adding subsystems to T-Kernel. Allows both lightweight and advanced systems on the same kernel T-Kernel Extensions provide: Virtual Memory: Using MMU, create multiple virtual address spaces Process Management functions: to modularize programs Event Management functions: for mouse, keyboard, etc File management functions Back to Classification

19. A N T S 19 Increasing Middle. ~ Porting Act. Other systems hold a lot of software assets that could be very beneficial for the T-Engine Establish porting guidelines for reusing those assets Operate other systems on top of T-Kernel Examples: ITRON middleware, Windows CE.Net ITRON Middleware 20 years of embedded development to reuse System call level highly compatible Porting main changes: Change in and reuse the Kernel API Changes to improve distribution (T-Format, Subsystems…)

20. A N T S 20 Increasing Middle. ~ Porting Act. Hybrid mechanism of T-Kernel and other OS: T-Bus Provide Real-Time functionality to other OS Benefit from the guest OS capabilities (interoperation, GUI, etc) Digital Video Camera Example Hybrid implementation

21. A N T S 21 Increasing Middle. ~ Porting Act. Linux Kernel on top of T-Kernel Light-Weight Object Oriented programming framew.Middleware for third-generation mobile phones T-Windows J2ME with T-engine profiles Windows CE.Net

22. A N T S 22 Increasing Middle. ~ T-Collection Basic set of software that runs on T-engine and T-kernel Standard format that makes easy to run code immediately Basic modules such as algorithms or large-scale practical software They are assumed to be Open-source Source code or binaries offered by T-Engine Forum Distributed with T-Dist Example of Collection: Small library containing tree programs Sorting function Searching function Encryption and Signatures Data compression algorithms Basic resident programs (i.e TCP/IP, file system based on allocation tables)

23. A N T S 23 Increasing Middle. ~ T-Builder Standard development environment Ensures de portability of middleware and application software Reference development environment Vendors might provide better Development Environments compatible with T-Builder Adopted the GNU development environment Requirements Open Compatible with multiple CPUs

24. A N T S 24 Middleware Distrib. ~ T-Dist Distribute encrypted Software (binary) When the executable is run, the software is decrypted and billed using the eTron (License ticket) Prevent illegal use of Software Promoting Distribution Generation of the encrypted Software by the server License control using eTRON Software-specific License control

25. A N T S 25 Middleware Distrib. ~ T-Dist Target Systems Software Applications Subsystems Device Drivers Dynamic Libraries Contents Static Libraries Audio-Visual Software Electronic Book Examples Permit execution only on eTRON systems that store a certain encryption key Payment mechanism based in the number of times the software runs

26. A N T S 26 Middleware Distrib. ~ T-Dist Server Client / eTRON

27. A N T S 27 Middleware Distrib. ~ T-Dist Encrypted Middleware Format

28. A N T S 28 Middleware Distrib. ~ T-Dist Middleware Vendor T-engine Forum User Encrypted Use End of Use Software Registration Order Agreement (T-Engine Forum acts as Proxy) Delivery eTRON 16 bit CPU 16 Mb Address Space 4 Kb RAM 96 Kb ROM 32 Kb EEPROM eTRON/16 Chip

29. A N T S 29Conclusions T-Engine forum emphasize the standardization and distribution methodology of the middleware Dont directly provide software Encourage vendors to produce the software Easing development and interoperability Easing distribution Guarantying licensing Provision of tools for porting existing software as T- Engine middleware On top of the T-kernel