.¦Ìc/os- Ii Kernel And Its Application Money Detector

With the fast development of electronic technology,communication technology,and far-ranging application of the internet,embedded system is becoming hot in the field of IT.With the sustain increasing of need from people for the function of IT products,the embedded system with single-chip can't not meet the need of market any more day by day.As the typical representative of embedded system,financial facility bill acceptor urgently needs the porting of RTOS.At first,this paper introduces the concept of embedded system and Real Time Operating System,compares several popular RTOSes at present,then according to the characteristics of bill acceptor,μC/OS-Ⅱis chosen as the object of research to build the software system.By the detailed analysis ofμCOS-Ⅱkernel,including task management and scheduling,interrupt and clock,synchronization and communication between tasks,an improvement for the kernel's scheduling mechanism is introduced according to the trait of data acquisition task,bringing in the Time Slice Circular Scheduling algorithm.The mircrocontrollerμPSD3233B andμCOS-Ⅱare selected to design the bill acceptor.According to the quality of the mircrocontroller and system function we want,corresponding function modules of hardware are designed,and the RTOSμCOS-Ⅱis ported to the mircrocontroller.At the same time,on the application layer different application tasks are created according to the system function.A farther research into the customization of network protocol stack based on 51 single-chip andμCOS-Ⅱis made.Choosing RTL8019AS as network controller,we cut out and change the source code ofμCOS-Ⅱkernel and standard TCP/IP protocol stack according to the characteristics ofμCOS-Ⅱto realize basic network function,laying the ground for the bill acceptor's direct internet access.