【文章內(nèi)容簡介】
| H L LL LH H H H | H L LH H二、3線——8線譯碼器74138的真值表G1 G2* | C B A | Y0N Y1N Y2N Y3N Y4N Y5N Y6N Y7NX H | X X X | H H H H H H H HL X | X X X | H H H H H H H HH L | L L L | L H H H H H H HH L | L L H | H L H H H H H HH L | L H L | H H L H H H H HH L | L H H | H H H L H H H HH L | H L L | H H H H L H H HH L | H L H | H H H H H L H HH L | H H L | H H H H H H L HH L | H H H | H H H H H H H L三、顯示紅色的“E”時74138真值表R1R2R3R4R5R6R7R8ROW1=000000000ROW2=001111110ROW3=001000000ROW4=001111110ROW5=001000000ROW6=001000000ROW7=001111110ROW8=000000000四‘顯示綠色的“R”時74138真值表G1G2G3G4G5G6G7G8ROW1=001111100ROW2=0010100ROW3=001111100ROW4=001000000ROW5=001100000ROW6=001010000ROW7=001001000ROW8=001000100圖一 八進(jìn)制計(jì)數(shù)器模塊原理圖圖二 74138對點(diǎn)陣進(jìn)行行掃描模塊原理圖圖三 顯示紅