- 1、本文档共26页,可阅读全部内容。
- 2、原创力文档(book118)网站文档一经付费(服务费),不意味着购买了该文档的版权,仅供个人/单位学习、研究之用,不得用于商业用途,未经授权,严禁复制、发行、汇编、翻译或者网络传播等,侵权必究。
- 3、本站所有内容均由合作方或网友上传,本站不对文档的完整性、权威性及其观点立场正确性做任何保证或承诺!文档内容仅供研究参考,付费前请自行鉴别。如您付费,意味着您自己接受本站规则且自行承担风险,本站不退款、不进行额外附加服务;查看《如何避免下载的几个坑》。如果您已付费下载过本站文档,您可以点击 这里二次下载。
- 4、如文档侵犯商业秘密、侵犯著作权、侵犯人身权等,请点击“版权申诉”(推荐),也可以打举报电话:400-050-0827(电话支持时间:9:00-18:30)。
查看更多
Copyright 2008 Koren ECE666/Koren Part.6a.* Israel Koren Spring 2008 UNIVERSITY OF MASSACHUSETTS Dept. of Electrical Computer EngineeringDigital Computer Arithmetic ECE 666 Part 6a High-Speed Multiplication - I Speeding Up Multiplication Multiplication involves 2 basic operations - generation of partial products + their accumulation 2 ways to speed up - reducing number of partial products and/or accelerating accumulation 3 types of high-speed multipliers: Sequential multiplier - generates partial products sequentially and adds each newly generated product to previously accumulated partial product Parallel multiplier - generates partial products in parallel, accumulates using a fast multi-operand adder Array multiplier - array of identical cells generating new partial products; accumulating them simultaneously No separate circuits for generation and accumulation Reduced execution time but increased hardware complexity Reducing Number of Partial Products Examining 2 or more bits of multiplier at a time Requires generating A (multiplicand), 2A, 3A Reduces number of partial products to n/2 - each step more complex Several algorithm which do not increase complexity proposed - one is Booths algorithm Fewer partial products generated for groups of consecutive 0’s and 1’s Booth’s Algorithm Group of consecutive 0’s in multiplier - no new partial product - only shift partial product right one bit position for every 0 Group of m consecutive 1s in multiplier - less than m partial products generated ...01…110... = ...10...000... - ...00...010... Using SD (signed-digit) notation =...100...010... Example: ...011110... = ...100000... - ...000010... = ...100010... (decimal notation: 15=16-1) Instead of generating all m partial products - only 2 partial products generated First partial product added - second subtracted - number of single-bit shift-right operations still m - - Booth’s Algorithm - Rules Recoding multiplier xn-1 xn- 2...x1 x0 in SD c
您可能关注的文档
- HACCP的现状与趋势以及在我国的发展建议课件.ppt
- Hacking Windows 2K, XP课件.PPT
- Handbook of Quantitative Finance and Risk Management课件.ppt
- HBV DNA定量检测课件.ppt
- Health Risk of Radiofrequency RadiationToxicological and 课件.ppt
- Heavy Duty On-Board Diagnostics课件.ppt
- Hedging Risk课件.ppt
- help people do the most unpleasant jobs课件.ppt
- Hemorrhagic Fevers课件.ppt
- HHB 5-5 ADA课件.ppt
文档评论(0)