期末復習比較器chenyu

1、6.9 Comparators（比較器）6.10 Adders, Subtractors, and ALUs(加減器和算術邏輯單元)6.9 comparator（比較器）(P458)比較2個二進制數(shù)值并指示其是否相等的電路等值比較器：檢驗數(shù)值是否相等數(shù)值比較器：比較數(shù)值的大?。?=,B（A=1, B=0）則 AB=1 可作為輸出信號 AB3)LT = EQ GT = ( EQ + GT )或 (A3 = B3) (A2 = B2) (A1B1)或 (A3 = B3)(A2 = B2)(A1 = B1) (A0B0)或 (A3 = B3) (A2B2)A3 B3A2 B2A1 B1A0 B0+輸

2、出高有效!74x856.9.4 Standard MSI Comparatorsthe 74x85 4-bit comparator A0A1A2A3ALTBINAEQBINAGTBIN級聯(lián)輸入，用于擴展ALTBOUT = (AB高位A高位=B高位 & A低位B低位ABAEQBOUT = (A=B)AEQBINAGTBOUT = (AB) + (A=B)AGTBIN74X85Serial Expanding Comparators(比較器的串行擴展)XD11:0YD11:03:07:411:8XY+5VABIABOA0A3B0B374x85ABIABOA0A3B0B374x85ABIABOA0

3、A3B0B374x853片74x85構成12位比較器低位高位Digital Logic Design and Application (數(shù)字邏輯設計及應用)8-bit comparator 74x682 (P463)P0P1P2P3P4P5P6P78-bit comparator 74x682(P463)問題1：怎樣用輸出來表示下列條件？ DIFF高電平有效：P DIFF Q EQ高電平有效：P EQ Q GE高電平有效：P GE Q LT高電平有效：P LT Q （P463 Figure 6-80）GELT問題2：能否擴展？注意：沒有級聯(lián)輸入端3片74x682構成24位比較器P0P7 P=Q

4、Q0Q7 PQP0P7 P=QQ0Q7 PQP0P7 P=QQ0Q7 PQ7:015:823:16P23:0Q23:0PEQQPGTQParalel Expanding Comparators(比較器的并行擴展)exercise Design a circuit to compare three 4-bit binary numbers A(a3a2a1a0), B(b3b2b1b0), C(c3c2c1c0) with two 4-bit comparators 74X85. You need to give three outputs: Fequal, FAmax, FAmin. Fequal =1 indicates A=B=C; FAmax =1 indicates A is the biggest one among them; FAmin =1 indicates A is the smallest one among them. Show your work. (Y