第11期 徐思成:同步时序逻辑电路设计新法 以上设计结果与文献/2/中的结论完全一致 。 4结束语 本文提出了一种直接从状态图上求触发器的 置位、复位函数,进而确定FF激励方程的新方法 图5逻辑电路图 设计同步时序逻辑电路.与传统设计方法相比 0/0 该方法简便、快捷,特别适合于采用JKFF和T FF的设计方案而且从上述设计实例中可看出设 K/y 0/0 1/0 计结果正确、可靠,对所有同步时序电路设计具有 普遍适用性 参考文献 图6完整状态转换图 []康华光,邹寿彬.电子技术基础(数字部分)[M]北 京高等教育出版社,2000 此例若采用TFF实现,则驱动方程为 [2]阎石.数字电子技术基础[M].北京高等教育出 F:=SF2+RF1=X·Q2Q 版社,1989 [3]何超,于席桂.计算机电路基础[M].北京:中国水 SFF,+ RFE,=X22 01+21=X22+ o 利水电出版社,2002 逻辑电路图略 [4]刘宝琴,沈雅芬.计算机电路基础(1)[M].北京:中 央广播电视大学出版社,2002 Design ing synchronours sequential logic circuits (Department of Quantity Examination, Henan Quantity Engineering Vocation College, Pingdingshan 467002, China) Abstract The new method of designing synchronours sequential logic circuits is put forward. Accord- ing to the basic characteristic of flip-flop circuit, the set-reset functions are got directly from state transition diagram, and the driver function can be made sure. Concrete actual examples show that the method is simr ple, fast, efficiently, and the designing electric circuit function is right Key words: synchronours sequential logic circuits; flip-flop circuit; state transition diagram (上接第8页) Experiment of measuring electronic property of solar cells MAO Qing-qing, PAn Lidong, ChEN Junyi, LU Shenr-long Department of Physics, Fudan University, Shanghai 200433, China) Abstract g photometer and color filters, the traditional method of measuring the l-U characteris tic of solar cells is improved, and the electric properties of the semiconductor solar cells used in different cir cumstances of illumination are measured. Meanwhile the forbidden band width of the semiconductor mater als is obtained Key words: solar cells; opencircuit voltage; short-circuit current; filling factor; forbidden band width 2 01995-2005 Tsinghua Tongfang Optical Disc Co, LId Al rights reserved.图 5 逻辑电路图 图 6 完整状态转换图 此例若采用 T2FF 实现 ,则驱动方程为 TFF2 = S FF2 + R FF1 = X·Q n 2 Q n 1 + XŠ·Q n 2 TFF1 = S FF1 + R FF1 = X Q n 2 Q n 1 + Q n 1 = X Q n 2 + Q n 1 逻辑电路图略. 以上设计结果与文献[2 ]中的结论完全一致. 4 结束语 本文提出了一种直接从状态图上求触发器的 置位、复位函数 ,进而确定 FF 激励方程的新方法 设计同步时序逻辑电路. 与传统设计方法相比 , 该方法简便、快捷 ,特别适合于采用 J K2FF 和 T2 FF 的设计方案 ,而且从上述设计实例中可看出设 计结果正确、可靠 ,对所有同步时序电路设计具有 普遍适用性. 参考文献 : [1 ] 康华光 ,邹寿彬. 电子技术基础(数字部分) [ M ]. 北 京 :高等教育出版社 , 2000. [2 ] 阎石. 数字电子技术基础[ M ]. 北京 :高等教育出 版社 ,1989. [3 ] 何超 ,于席桂. 计算机电路基础[ M ]. 北京 :中国水 利水电出版社 ,2002. [ 4 ] 刘宝琴 ,沈雅芬. 计算机电路基础(1) [ M ]. 北京 :中 央广播电视大学出版社 ,2002. Designing synchronours sequential logic circuits XU Si2cheng (Department of Quantity Examination , Henan Quantity Engineering Vocation College , Pingdingshan 467002 , China) Abstract : The new method of designing synchronours sequential logic circuits is put forward. Accord2 ing to the basic characteristic of flip2flop circuit , the set2reset functions are got directly from state transition diagram , and the driver function can be made sure. Concrete actual examples show that the method is sim2 ple , fast , efficiently , and the designing electric circuit function is right . Key words : synchronours sequential logic circuits ; flip2flop circuit ; state transition diagram (上接第 8 页) Experiment of measuring electronic property of solar cells MAO Qing2qing , PAN Li2dong , CHEN J un2yi , L U Shen2long (Department of Physics , Fudan University , Shanghai 200433 , China) Abstract : Using photometer and color filters , the traditional method of measuring the I2U characteris2 tic of solar cells is improved , and the electric properties of the semiconductor solar cells used in different cir2 cumstances of illumination are measured. Meanwhile the forbidden band width of the semiconductor materi2 als is obtained. Key words : solar cells ; open2circuit voltage ; short2circuit current ; filling factor ; forbidden band width 第 11 期 徐思成 :同步时序逻辑电路设计新法 11 © 1995-2005 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved