数字电路中有关教学内容和方法的探讨

由逻辑函数表达式画卡诺图时,首先根据变量个数画出变量的卡诺图,变量取值的循环码不填,只在格外标出各变量为1的取值范围.然后将表达式中乘积项逐个地填入卡诺图的小方格中.一个乘积项就是一组条件,凡是符合该组条件的方格都填1,其余方格留空,允许有的方格被重复填1.最后所有乘积项都填格完毕后,若看到卡诺图中有的方格还是空的,则在这些空格填0;若看到有的方格填了多个1,只保留一个1即可(正确的填法不应该出现一个方格既填1又填0的情况).

On Some Contents and Teaching Methods of Digital Circuit

There are three steps when drawing Karnaugh map according to logic function expression. First, the Karnaugh map of variables is drawn according to the number of the variables. Instead of the cyclic codes of the variables, the value range of the variable of 1 is marked outside the panes of the Karnaugh map. Then, the product terms of the expression are filled in the panes of the Karnaugh map respectively. Regarding one product term as a group of conditions, the pane which is conformed with the product term conditions is filled with 1, otherwise it is emptied. It is allowed that some panes are filled with 1 repeatedly. Finally, when all of the product terms are filled in the Karnaugh map, 0 is filled in the pane which is empty, and only one 1 is preserved in the panes which are filled with 1 more than once .(It is incorrect that a pane is fill with 1 as well as filled with 0.)