一种自定时的前置进位加法器设计

从时序控制的角度出发,研究提高加法器性能的方法。在研究前置进位加法器的算法和结构后,又对多米诺电路的时钟控制技术进行深入分析。结合前置进位结构和自定时时钟控制．设计了一个32b多米诺加法器。该加法器能有效地提高时钟使用率。在TSMC0．18um工艺下,加法器的最大延时为970ps,约为相同工艺下13倍FO4的延时。     

异步零协议算术逻辑单元的设计

异步电路在低功耗、低噪声、抗干扰、无时钟偏移、高鲁棒性和模块化设计等方面有较高的性能.设计了一个异步4位8操作码的算术逻辑单元,使用了双轨延时不敏感零协议逻辑结构,同时比较了使用流水线结构和非流水线结构以及相关的面积和速度优势.结果显示平均速度最快的结构比非流水线结构快了1.73倍,而面积需要增加了133%.     

一种零协议逻辑全异步流水线电路的优化设计研究

This paper proposes a new optimization method to improve the performance of a null convention logic asynchronous pipeline.Parallel combinational logic modules in the pipelines can work alternately in null and data cycles by using a parallel processing mode.The complete waiting time for both null and data signals of combinational logic output in previous asynchronous register stage is reduced by decoupling the output from combinational logic modules.Performance penalty brought by null cycle is reduced while the data processing capacity is increased.The novel asynchronous pipeline based on asynchronous full adders with different bit widths as asynchronous combination logic modules is simulated using 0.18-μm CMOS technology.Based on 6 bits asynchronous adder as asynchronous combination logic modules, the simulation result of this new pipeline proposal demonstrates a high throughput up to 72.4% improvement with appropriate power consumption.This indicates the new design proposal is preferable for high-speed as ynchronous designs due to its high throughput and delay-insensitivity.     

Optimization design of a full asynchronous pipeline circuit based on null convention logic

peed asynchronous designs due to its high throughput and delay-insensitivity.     

忆阻器实现逻辑门的方法研究

在分析忆阻器特性及相关文献的基础上提出了一种只使用忆阻器元件实现基本逻辑门的电路方案,理论分析及Spice仿真实验结果证实了方案的可行性．所设计的逻辑门电路简单,实现的逻辑门无需时序操作就能工作,其在电路尺寸、集成密度、电路功耗等方面拥有很大的优势．     

Approach to partially self-checking combinational circuits design

This paper presents a cost-effective, non-intrusive technique of partially self-checking combinational circuits design. The proposed technique is similar to duplication with comparison, wherein duplicated function module and comparator act as a function checker that detects any erroneous response of the original function module. However, instead of realizing checker with full error-detection capability, we select a subset of erroneous responses to implement partial, but simplified function checker. A heuristic procedure that tries to find the optimal sum-of-product expression for partial function checker that minimizes its area while providing specified error coverage is described here. Effectiveness of the technique is evaluated on a set of MCNC 91 benchmark combinational circuits.     

关于异步时序逻辑电路的讨论──从《数字逻辑》教材中的一道错误例题谈起

本文从《数字逻辑》现行教材中的一个典型错例出发，根据对数字逻辑电路多年的教学经验，对异步时序逻辑电路部分的一些概念和方法提出了自己的看法，并作了详细的讨论。     

基于FSM的自动售货机的设计与实现

设计了一种基于FSM的自动售货机实现方案。设计使用VHDL语言编写各控制模块,充分利用有限状态机描述自动售货机各个执行过程,包括系统初始化、管理员设置、商品选择、确认取消、投币处理、金额统计、货品更新及余额找零等一系列动作。同时,系统还添加了按键编码模块、扫描显示模块及语音提示模块,使得用户操作更加人性化。     

一种可逆有限状态机的电路设计

不同以往通过重构电路行为实现可逆有限状态机方法,本文提出了一种可逆有限状态机的电路结构.该电路主要包括次态与输出计算电路以及状态预置与采样锁存电路两部分,且提出的可逆有限状态机电路中不存在独立的可逆触发器,但可以实现可逆JK,D,T等触发器功能.同时,文中也提出了基于该可逆有限状态机电路的可逆时序电路综合方法,并用实例进行了验证.相比于基于行为重构的可逆有限状态机的综合方法,本文提出的综合方法可以避免原始状态机的逆状态机的求解和增加额外的信号位,从而使得综合过程变得更加简单.     

Signal‐Dependent Chaotic‐State‐Modulated Digital Secure Communication

In this letter, a discrete state, discrete time chaotic pseudo random number generator (CPRNG) is presented for stream ciphering of text, audio, or image data. The CPRNG is treated as a finite state machine, and its state is modulated according to the input bit sequence of the signal to be encrypted. The modulated state sequence obtained can be transmitted as a spread spectrum or encrypted data.     

用可编程逻辑器件进行组合电路设计时的延时分析

随着高校EDA教学的不断深入,学生往往只注重设计工具、编程语言的熟练程度,而忽视了电路设计中的一些基本问题。本文详细分析了组合电路中延时错误产生的原因,并提出了三种解决方法。     

具有动态检测功能的彩色九画面处理器的设计与实现

描述了具有动态检测功能的彩色多画面处理器的软硬件设计思路和实现途径.针对软件设计的复杂性,采用基于有限状态机的软件设计方法,来提高系统软件的可靠性和代码的重用性,测试结果表明系统实现了预定功能.     

Monitoring machine based synthesis technique for concurrent error detection in finite state machines

This paper discusses a new design methodology for concurrent error detection in synchronous sequential circuits based on the use of monitoring machines. In this approach, an auxiliary sequential circuit, called the monitoring machine, operates in lock-step with the main machine, such that any fault in either of the two machines is immediately detected. This methodology is independent of the fault model. It can be applied to FSMs with pre-encoded states and can also be used for ones being synthesised. It also provides a systematic framework for the combined optimisation of the main and monitoring machines, and for exploring tradeoffs in their implementation. The design of monitored sequential circuits is a two-fold problem; namely one of designing an optimal monitoring machine given the main machine, and the other of encoding the main machine states so that the resulting monitoring machine is minimal. This paper formally discusses the design of both the main and monitoring machines and techniques for their combined optimisation. Tradeoffs in their implementation based on selective fault detection are also examined. Through experimental results, it is shown that the proposed synthesis technique is eminently suitable for the design of low-cost sequential circuits with concurrent error detection. The monitoring machine is less costly than the main machine. It is also not identical to it. As a result, a monitored sequential circuit has significantly lower hardware cost and improved fault coverage than previous implementations. Presently at Texas Instruments (India) Ltd., Bangalore, India.     

异步时序逻辑电路的设计方法探讨

在传统的同步时序电路设计方法的基础上,提出了一种新的异步时序电路的设计方法。该方法直接从时序电路的时序波形图,获得触发器的触发脉冲;根据时钟信号作用下引起的状态转换,填写次态卡诺图。其特点是原理简单,易于理解,使设计更加直观清楚。     

异步Viterbi解码器同步接口的设计

提出了一种利用异步 FIFO ( First In First Out)连接异步逻辑电路与同步逻辑电路的方法 ,并设计实现了相应的异步 FIFO电路 ,作为连接异步 viterbi解码器和其他同步逻辑电路的同步接口。对异步 FIFO的级数与异步 viterbi解码器内部的时序关系进行了分析。用逻辑仿真的动态时序分析表明 ,当同步电路时钟的周期大于 130 ns时 ,具有同步接口的异步 viterbi解码器可以与同步电路正常协同工作。具有简单接口电路的异步解码器 ,既能发挥异步电路功率效率高的优点 ,而且能嵌入同步电路系统     

一个基于知识的通信有限状态机生成器

通信有限状态机(CFSM)是一种直观、易懂且描述能力较强的形式描述工具。它被广泛地用来描述通信协议等。但是,由于描述对象的复杂性和缺少适当的支援工具,通信有限状态机的生成一般依靠手工完成。这除了效率低外,也使得所产生的CFSM的性能取决于描述人员的习惯、经验、能力等。本文描述一个基于知识的CFSM半自动生成器。该生成器用专家系统开发语言OPS83构成,能交互地生成两个不含常见逻辑错误的互相传递消息的CFSM。另外,该生成器还以友好的用户接口:(图形、颜色、文字等方式)向用户展示CFSM的生成过程和生成结果。     

基于FPGA的UART设计

UART作为RS232协议的控制接口得到了广泛的应用,将UART的功能集成在FPGA芯片中,可使整个系统更为灵活、紧凑,减小整个电路的体积,提高系统的可靠性和稳定性。提出了一种基于FPGA的UART的实现方法,具体描述了发送、接收等模块的设计,恰当使用了有限状态机,实现了FPGA片上UART的设计,给出了仿真结果。     

基于FPGA的UART设计实现及其验证方法

UART作为RS 232协议的控制接口得到了广泛的应用,基于FPGA实现的UART设计可以使系统更加紧凑、稳定.系统结构进行了模块化分解,使之适应自顶向下(Top Down)的设计方法.核心部分采用有限状态机(FSM)实现,使控制逻辑直观简单,提高了设计效率.通过与计算机间的数据通信对设计的功能进行了验证,在此基础上衍生出一种将UART模块嵌入FPGA芯片与计算机互联进行功能验证和调试的新方法.     

Intermediate Representations for Design Automation of Multiprocessor DSP Systems

Self-timed scheduling is an attractive implementation style for multiprocessor DSP systems due to its ability to exploit predictability in application behavior, its avoidanceof over-constrained synchronization, and its simplified clocking requirements.However, analysis and optimization of self-timed systems under real-time constraintsis challenging due to the complex, irregular dynamics of self-timed operation.In this paper, we review a number of high-level intermediate representationsfor compiling dataflow programs onto self-timed DSP platforms, including representationsfor modeling the placement of interprocessor communication (IPC) operations;separating synchronization from data transfer during IPC; modeling and optimizinglinear orderings of communication operations; performing accurate design spaceexploration under communication resource contention; and exploring alternativeprocessor assignments during the synthesis process. We review the structureof these representations, and discuss efficient techniques that operate onthem to streamline scheduling, communication synthesis, and power managementof multiprocessor DSP implementations.     

虚拟项目教学法在组合逻辑电路教学中的应用

本文介绍虚拟项目教学法在组合逻辑电路教学中的应用。综合运用门电路、编码器、加法器、译码器等组合逻辑电路知识完成加法计算器的分析和设计。实践表明,借助Multisim12开展虚拟项目教学能够提高学生的自主学习能力和创新能力。