The Implementation Of TCP/IP Protocol Based On NiosII Softcore CUP

This thesis study mainly the scheme of implement TCP/IP protocol based on the NiosII softcore CPU. By analasizing the system archtechture of the CPU, it's compiler is satisfied with the condition of porting the Embedded Real-Time System uC/OS-II on it. The porting work includes the definition of data type, stack width and stack increase derection, the design of task stack space and task switch function. Task switch is mainly dealed with the preservation and comeback of CPU locale(Register), so it must be programmed by processor assemble language. By analyzing and simplifying of TCP/IP protocol,several basis protocols are implemented such as ARP(Address Resolution Protocol), IP(Internet Protocol), ICMP(Internet Control Message Protocol), UDP(User Datagram Protocol) and TCP(Transmission Control Protocol). The message queue is implemented by packating the message processing mechanism and memory management ofμC/OS-II. It can be used for the TCP/IP protocol stack to buffering and transmitting the data packet, which makes the protocol stack runs onμC/OS-II. CS8900A is used as lower layer network chip and it's driver is completed. By packeting the UDP and TCP, the application program interface is also completed, which can be called by higher layer application program.