The PCA9670 provides general purpose remote I/O expansion for most microcontrollerfamilies via the two-line bidirectional bus (I2C-bus) and is a part of the Fast-mode Plusfamily.The PCA9670 is a drop-in upgrade for the PCF8574 providing higher Fast-mode Plus(Fm+) I2C-bus speeds (1 MHz versus 400 kHz) so that the output can support PWMdimming of LEDs, higher I2C-bus drive (30 mA versus 3 mA) so that many more devicescan be on the bus without the need for bus buffers, higher total package sink capacity(200 mA versus 100 mA) that supports having all 25 mA LEDs on at the same time andmore device addresses (64 versus 8) are available to allow many more devices on the buswithout address conflicts.
上传时间： 2013-10-15
上传用户：stella2015
The PCA9671 provides general purpose remote I/O expansion for most microcontrollerfamilies via the two-line bidirectional bus (I2C-bus) and is a part of the Fast-mode Plus(Fm+) family.The PCA9671 is a drop in upgrade for the PCF8575 providing higher I2C-bus speeds(1 MHz versus 400 kHz) so that the output can support PWM dimming of LEDs, higherI2C-bus drive (30 mA versus 3 mA) so that many more devices can be on the bus withoutthe need for bus buffers, higher total package sink capacity (400 mA versus 100 mA) thatsupports having all 25 mA LEDs on at the same time and more device addresses (64versus 8) to allow many more devices on the bus without address conflicts.
上传时间： 2013-10-12
上传用户：laomv123
The PCA9672 provides general purpose remote I/O expansion for most microcontrollerfamilies via the two-line bidirectional bus (I2C-bus) and is a part of the Fast-mode Plusfamily.The PCA9672 is a drop-in upgrade for the PCF8574 providing higher Fast-mode Plus(Fm+) I2C-bus speeds (1 MHz versus 400 kHz) so that the output can support PWMdimming of LEDs, higher I2C-bus drive (30 mA versus 3 mA) so that many more devicescan be on the bus without the need for bus buffers, higher total package sink capacity(200 mA versus 100 mA) that supports having all LEDs on at the same time and moredevice addresses (16 versus 8) are available to allow many more devices on the buswithout address conflicts.
上传时间： 2013-10-23
上传用户：jasonheung
The PCA9673 provides general purpose remote I/O expansion for most microcontrollerfamilies via the two-line bidirectional bus (I2C-bus) and is a part of the Fast-mode Plusfamily.The PCA9673 is a drop in upgrade for the PCF8575 providing higher Fast-mode Plus(Fm+) I2C-bus speeds (1 MHz versus 400 kHz) so that the output can support PWMdimming of LEDs, higher I2C-bus drive (30 mA versus 3 mA) so that many more devicescan be on the bus without the need for bus buffers, higher total package sink capacity(400 mA versus 100 mA) that supports having all 25 mA LEDs on at the same time andmore device addresses (16 versus 8) are available to allow many more devices on the buswithout address conflicts.
上传时间： 2013-10-29
上传用户：wkchong
Internal Interrupts are used to respond to asynchronous requests from a certain part of themicrocontroller that needs to be serviced. Each peripheral in the TriCore as well as theBus Control Unit, the Debug Unit, the Peripheral Control Processor (PCP) and the CPUitself can generate an Interrupt Request.So what is an external Interrupt?An external Interrupt is something alike as the internal Interrupt. The difference is that anexternal Interrupt request is caused by an external event. Normally this would be a pulseon Port0 or Port1, but it can be even a signal from the input buffer of the SSC, indicatingthat a service is requested.The User’s Manual does not explain this aspect in detail so this ApNote will explain themost common form of an external Interrupt request. This ApNote will show that there is aneasy way to react on a pulse on Port0 or Port1 and to create with this impulse an InterruptService Request. Later in the second part of the document, you can find hints on how todebounce impulses to enable the use of a simple switch as the input device.Note: You will find additional information on how to setup the Interrupt System in theApNote “First steps through the TriCore Interrupt System” (AP3222xx)1. It would gobeyond the scope of this document to explain this here, but you will find selfexplanatoryexamples later on.
上传时间： 2013-10-27
上传用户：zhangyigenius
The Infineon TriCore provides an Interrupt System with a high safety standard. Thisdocument contains some instructions on how to initiate an Interrupt from an externaldevice. First it will show you how to trigger an Interrupt Service Request by an impulseon Port 0 or Port 1. Then in the second part of the document you can find hints how todebounce impulses to enable the use of a simple switch as input device.Authors: Thomas Bliem, CQ Nguyen / Infineon SMI MD Apps
上传时间： 2013-11-05
上传用户：uuuuuuu
The standard that governs the design of avioniccomponents and systems, DO-254, is one of the mostpoorly understood but widely applicable standardsin the avionic industry. While information on thegeneral aspects of the standard is easy to obtain, thedetails of exactly how to implement the standard aresketchy. And once an entity develops a process thatachieves compliance, the details of how compliancewas achieved become part of the intellectualproperty of that entity. This white paper focuses onthe details of developing a DO-254 compliantprocess for the design of FPGAs.
上传时间： 2013-11-12
上传用户：q123321
Field Programmable Gate Arrays (FPGAs) are becoming a critical part of every system design. Many vendors offer many different architectures and processes. Which one is right for your design? How do you design one of these so that it works correctly and functions as you expect in your entire system? These are the questions that this paper sets out to answer.
上传时间： 2013-10-29
上传用户：lixqiang
摘要: 串行传输技术具有更高的传输速率和更低的设计成本, 已成为业界首选, 被广泛应用于高速通信领域。提出了一种新的高速串行传输接口的设计方案, 改进了Aurora 协议数据帧格式定义的弊端, 并采用高速串行收发器Rocket I/O, 实现数据率为2.5 Gbps的高速串行传输。关键词: 高速串行传输; Rocket I/O; Aurora 协议 为促使FPGA 芯片与串行传输技术更好地结合以满足市场需求, Xilinx 公司适时推出了内嵌高速串行收发器RocketI/O 的Virtex II Pro 系列FPGA 和可升级的小型链路层协议———Aurora 协议。Rocket I/O支持从622 Mbps 至3.125 Gbps的全双工传输速率, 还具有8 B/10 B 编解码、时钟生成及恢复等功能, 可以理想地适用于芯片之间或背板的高速串行数据传输。Aurora 协议是为专有上层协议或行业标准的上层协议提供透明接口的第一款串行互连协议, 可用于高速线性通路之间的点到点串行数据传输, 同时其可扩展的带宽, 为系统设计人员提供了所需要的灵活性[4]。但该协议帧格式的定义存在弊端,会导致系统资源的浪费。本文提出的设计方案可以改进Aurora 协议的固有缺陷,提高系统性能, 实现数据率为2.5 Gbps 的高速串行传输, 具有良好的可行性和广阔的应用前景。
上传时间： 2013-11-06
上传用户：smallfish
在现代通信系统中，电话语音的频带被限制在300 Hz～4 kHz的范围内，带来了语音可懂度和自然度的降低。为了在不增加额外成本的前提下提高语音的可懂度和自然度，进行了电话语音频带扩展的研究。提出了一种改进的基于码本映射的语音带宽扩展算法：在码本映射的过程中，使用加权系数来得到映射码本。客观测试结果表明，用此算法得到的宽带语音的谱失真度比用一般的码本映射降低至少2%。主观测试结果表明，用此算法得到的宽带语音具有更好的可懂度和自然度。 Abstract: In modern communication systems， the bandwidth of telephone speech is limited from 300Hz to 4 kHz， which reduces the intelligibility and naturalness of speech. Telephone speech bandwidth extension is researched to get wideband speech and to improve its intelligibility and naturalness， without increasing extra costs. This paper put forward an improved algorithm of speech bandwidth extension based on codebook mapping. In the process of codebook mapping， weighted coefficients were used to get mapping codebook. Objective tests show that spectral distortion of wideband speech obtained by this algorithm reduces at least 2%， comparing to conditional codebook mapping. Subjective tests show that the wideband speech obtained by this algorithm has better intelligibility and naturalness.
上传时间： 2014-12-29
上传用户：15501536189
