The Design And Implement Of IP Intelligent Agent Based On Embedded System μC/OS-Ⅱ

The project of digital speech classroom needs at least three components of the H.323. The gatekeeper is the handler of the whole speech classroom, which provides four basic services: address translation, bandwidth control, admission control and zone management. It is in charge of user's login, registration, bandwidth distribution and database interface etc. on the student terminal. Multipoint Control Unit support conferences between three or more endpoints in a multipoint conference. It shall consist of an MC and zero or more MPs. MP processes audio signals respectively which comes from the student terminals and returns their mixing to the original terminal, which shows the atmosphere of the conference. MC provides the control function of multipoint communication and selects the communication mode. Student Terminal is an IP intelligent terminal based on μC/OS-II, which can be connected with teacher computer, and Switch though twisted-pair. It makes the acoustics of the system more perfect because real-time implementation of speech coder algorithm in the DSP. This paper studies and designs two H.323 components: MCU and Based-μC/OS-II IP intelligent terminal.MCU run in teacher computer which changes the logic connections of the student terminal according to the requirement of teaching administration, and to implement state switching such as broadcast, dialog, group discussion and order broadcasting etc. MCU in H.323 must be adjusted greatly to adaptto the special application in speech classroom. In this paper, the MCU source code is enlarged necessarily and compiled on Linux platform to pass after analyzing the H.323 protocol generally. It implements most of functions such as the broadcasting teaching, random teaching group discussion, audio order program freely and electric system of inquiry etc.Student terminal adopts TI dual-core processor TMS320VC5471, which integrates a 16-bit fixed point DSP (100MIPS) subsystem and 32-bit RISC micro-controller subsystem. Media access control (MAC) on Ethernet linker layer,μC/OS-II operation system and TCP/IP protocol are embedded in this chip, which compose the IP intelligent terminal. In the research, The system Boot procedure is designed after analyzing all the characteristics of the TMS320VC5471 EVM. OS_CPU.H, OS_CPU_A.C, OS_CPU_A.ASM of these three procedures are programmed according to the EVM after studying all the C cores in the μC/OS-H Design and debug of the assembly language about the target processor are implemented. By CCS development platform mixing compile and link technique,μC/OS-II is integrate with initialization source codes of system into a full apply. TCP/IP protocol and interface drivers are enlarged such as audio I/O, Keyboard, LCD and Ethernet Transceivers etc. Ultimately, based on all the above works, H.323 terminal modules on the IP terminals are implemented. These modules can be used in IP phone terminal and distance controller terminal based on IP etc.