首先分析Chirp函数在频域上的一般特性,并且分析Altrea公司提供的数控振荡器知识产权核(NCO IP core)的输入/输出特性,通过MegaCore环境确定其输入控制字,通过外围逻辑电路实时向NCO IP core调入控制频率控制字以达到改变输出频率的目的...首先分析Chirp函数在频域上的一般特性,并且分析Altrea公司提供的数控振荡器知识产权核(NCO IP core)的输入/输出特性,通过MegaCore环境确定其输入控制字,通过外围逻辑电路实时向NCO IP core调入控制频率控制字以达到改变输出频率的目的,并通过在示波器上观测FPGA的运行情况,验证了该设计具有很好的输出效果。展开更多
As remote control for electric home appliances thro ug h the Internet becomes more common, many compannies today launched a new corpora te initiative to develop advanced embedded solutions for Internet connectivity t ...As remote control for electric home appliances thro ug h the Internet becomes more common, many compannies today launched a new corpora te initiative to develop advanced embedded solutions for Internet connectivity t hat can be applied to a boundless number of products such as information applian ces and non-PC devices. The most representative products are CMX-MicroNet which provides true TCP/IP ca pabilities for 8-bit and 16-bit microprocessors and eZ80Internet Engine which provides easy Internet connectivity for 8-bit devices. Pushed by the extraordinary success of these products, we have developped a kin d of embedded TCP/IP chip based on DW8051 Core.With some significant features su ch as establishing several connections at a same time, low-cost and high speed, we hope it will possess its own "embedded Internet" market. There are three most common application fields of the embedded TCP/IP chip. a) connection embedded microcontroller-based devices such as electric home appl iances to Internet b) allowing the remote control and monitoring of devices in the field via the In ternet c) allowing a remote device to send messages via email to, for example, a servic e centre. The working process of communication with embedded TCP/IP chip is described as f ollows.When it starts to work, it keeps on waiting the connection request from t he host and getting the requisite information such as destination IP address,des tination port through the host interface.Then it should connect to the ISP. A di al-up modem makes the connection and then the connection is negotiated. When bo th end systems begin to communicate, the chip keeps on transmitting datagram bet ween them and inspecting every phase of the connection to ensure the communicati on. The innovation of this design is the successful usage of separate CRC module and UART module, as can improve the speed and performance of this chip greatly. Suc h kind of efficiency improvement brought by the proposed design has been proved on Altera’s SOPC(System On a Programmable Chip). The whole system has been val idated through hardware emulation platform. The core has been mapped on APEX EP2 0K400E and works under the frequency of 25 MHZ.展开更多
文摘首先分析Chirp函数在频域上的一般特性,并且分析Altrea公司提供的数控振荡器知识产权核(NCO IP core)的输入/输出特性,通过MegaCore环境确定其输入控制字,通过外围逻辑电路实时向NCO IP core调入控制频率控制字以达到改变输出频率的目的,并通过在示波器上观测FPGA的运行情况,验证了该设计具有很好的输出效果。
文摘As remote control for electric home appliances thro ug h the Internet becomes more common, many compannies today launched a new corpora te initiative to develop advanced embedded solutions for Internet connectivity t hat can be applied to a boundless number of products such as information applian ces and non-PC devices. The most representative products are CMX-MicroNet which provides true TCP/IP ca pabilities for 8-bit and 16-bit microprocessors and eZ80Internet Engine which provides easy Internet connectivity for 8-bit devices. Pushed by the extraordinary success of these products, we have developped a kin d of embedded TCP/IP chip based on DW8051 Core.With some significant features su ch as establishing several connections at a same time, low-cost and high speed, we hope it will possess its own "embedded Internet" market. There are three most common application fields of the embedded TCP/IP chip. a) connection embedded microcontroller-based devices such as electric home appl iances to Internet b) allowing the remote control and monitoring of devices in the field via the In ternet c) allowing a remote device to send messages via email to, for example, a servic e centre. The working process of communication with embedded TCP/IP chip is described as f ollows.When it starts to work, it keeps on waiting the connection request from t he host and getting the requisite information such as destination IP address,des tination port through the host interface.Then it should connect to the ISP. A di al-up modem makes the connection and then the connection is negotiated. When bo th end systems begin to communicate, the chip keeps on transmitting datagram bet ween them and inspecting every phase of the connection to ensure the communicati on. The innovation of this design is the successful usage of separate CRC module and UART module, as can improve the speed and performance of this chip greatly. Suc h kind of efficiency improvement brought by the proposed design has been proved on Altera’s SOPC(System On a Programmable Chip). The whole system has been val idated through hardware emulation platform. The core has been mapped on APEX EP2 0K400E and works under the frequency of 25 MHZ.