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With the fast development of Internet technology and embedded systems, the Embedded Internet Technology is being widely applied to more and more fields. In 2004, FREESCALE provided MC9S12NE64, a low-cost,16-bit, S12 serial MCU, which can be connected to the Internet with a single chip. The MC9S12NE64 integrates an Ethernet controller that includes a media access controller (MAC) and a physical transceiver (PHY), so it is compliant to IEEE802.3. As a universal Ethernet-connected chip, this chip can work in full-duplex mode and half-duplex mode, and can implement 10/100Mbps Ethernet network. What’s more, it can support auto-negotiation, too. MC9S12NE64 can be compliant to a third TCP/IP stack. It’s core-speed is up to 50MHz. This chip is integrated with 8K RAM,64K Flash and an 8-channel, 10-bit ADC module. The same to other MCUs, several serial communication interfaces can be provided in this chip, such as UART, SPI, IIC. So, MC9S12NE64 is a good choice for an economical Embedded Internet System.FREESCALE selects an open source TCP/IP stack for MC9S12NE64, OpenTCP. OpenTCP is a TCP/IP stack implementation that is tailored for 8-bit and 16-bit embedded processors. The paper describes the migration of OpenTCP TCP/IP stack to MC9S12NE64, including two parts, hardware and software. The system implements some usual TCP/IP protocols, such as ICMP, UDP, TCP, HTTP, etc, and connects some simple peripheral equipment such as a temperature measurement circruit and an EEPROM device through GPIO, A/D and IIC. What’s more the software implements CGI function in the web pages, so the system can support dynamic web page function. Therefore, user can control remote equipments in a web browser. The paper provides a scheme for information appliance to connect to Internet without extra PC or gateway. The low-cost and hign-performance scheme has the advantage of reliability and agility. It can be applied to automation devices without requiring fast communication speed.The result of this experiment shows that the system can transmit data steadily with good performance, and can be fit to the demand of system, so it has a wide application prospect.
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