2014電航&同舟Class2：編碼器譯碼器本科內(nèi)容：編碼&譯碼&數(shù)碼管復(fù)習(xí)

7448芯片應(yīng)用一起點(diǎn)亮一個(gè)數(shù)碼管顯示幾個(gè)數(shù)字吧！

D&JK初步認(rèn)識(shí)觸發(fā)器編碼器&譯碼器熟悉真值表2-4譯碼器最簡(jiǎn)單的一種INOUTEA1A0O0O1O2O31XX11110000111001101101011010111110示意圖&真值表：INOUTEA1A0O0O1O2O31XX11110000111001101101011010111110示意圖&真值表：INOUTEA1A0O0O1O2O31XX11110000111001101101011010111110示意圖&真值表：24譯碼器嵌套：3-8譯碼器試著用2個(gè)24譯碼器示意圖&真值表：INOUTA2A1A0Y0Y1Y2O3O4O5O6O7XXX111111110000111111100110111111010110111110111110111110011110111101111110111101111110111111111110示意圖&真值表：INOUTA2A1A0Y0Y1Y2O3O4O5O6O7XXX111111110000111111100110111111010110111110111110111110011110111101111110111101111110111111111110示意圖&真值表：INOUTA2A1A0Y0Y1Y2O3O4O5O6O7XXX111111110000111111100110111111010110111110111110111110011110111101111110111101111110111111111110示意圖&真值表：INOUTA2A1A0Y0Y1Y2O3O4O5O6O7XXX111111110000111111100110111111010110111110111110111110011110111101111110111101111110111111111110741488-3優(yōu)先編碼器74148：示意圖&真值表：INOUTEI01234567A2A1A0GSEO1XXXXXXXX11111011111111111100XXXXXXX0000010XXXXXX01001010XXXXX011010010XXXX0111011010XXX01111100010XX011111101010X01111111100100111111111101擴(kuò)展：16-4優(yōu)先編碼器1：片選右側(cè)EI應(yīng)為多少？示意圖&真值表：INOUTEI01234567A2A1A0GSEO1XXXXXXXX11111011111111111100XXXXXXX0000010XXXXXX01001010XXXXX011010010XXXX0111011010XXX01111100010XX011111101010X01111111100100111111111101EI=0工作優(yōu)先級(jí)？從高到低15最高，0最低89101112131415高位片工作：891011121314158:15存在有效位089101112131415示意圖&真值表：INOUTEI01234567A2A1A0GSEO1XXXXXXXX11111011111111111100XXXXXXX0000010XXXXXX01001010XXXXX011010010XXXX0111011010XXX01111100010XX011111101010X01111111100100111111111101示意圖&真值表：INOUTEI01234567A2A1A0GSEO1XXXXXXXX11111011111111111100XXXXXXX0000010XXXXXX01001010XXXXX011010010XXXX0111011010XXX01111100010XX011111101010X01111111100100111111111101當(dāng)高位片均無效時(shí)：89101112131415低位片工作：891011121314152：輸出當(dāng)高位有效時(shí)高位正常輸出低位輸出均為1結(jié)論：高位有效時(shí)，輸出的A3應(yīng)該是多少？示意圖&真值表：INOUTEI89101112131415A2A1A0GSEO1XXXXXXXX11111011111111111100XXXXXXX0000010XXXXXX01001010XXXXX011010010XXXX0111011010XXX01111100010XX011111101010X01111111100100111111111101GS：示意圖&真值表：INOUTEI01234567A2A1A0GSEO1XXXXXXXX11111011111111111100XXXXXXX0000010XXXXXX01001010XXXXX011010010XXXX0111011010XXX01111100010XX011111101010X01111111100100111111111101示意圖&真值表：INOUTEI01234567A2A1A0GSEO1XXXXXXXX11111011111111111100XXXXXXX0000010XXXXXX01001010XXXXX011010010XXXX0111011010XXX01111100010XX011111101010X0111111110010011111111110116-4優(yōu)先編碼器他的作用？7448:4線-7段譯碼器74LS487448:4線-7段譯碼器74LS48一個(gè)0到F的數(shù)字的二進(jìn)制74LS48輸出，應(yīng)該接在哪里？74LS48數(shù)碼管：74LS48

BI/RBO：消隱輸入/脈沖消隱輸出

LT：燈測(cè)試輸入端

RBI：脈沖消隱輸入

功能引腳：演示Multisim13組合邏輯電路無記憶功能，輸入輸出觸發(fā)器有記憶功能基本RS鎖存器(觸發(fā)器)：RSQ!Q只有當(dāng)輸入改變時(shí)，輸出才改變：RSQ!QINOUTRSQnQn+100000011010101111000101011001110RS鎖存器：

只有輸入改變

輸出才改變RSQ!QD觸發(fā)器：INOUTDCLKQnQn+10X01X1X0XQnX1XQnD觸發(fā)器：邊沿觸發(fā)INOUTDCLKQnQn+10X01X1X0XQnX1XQnD觸發(fā)器：邊沿觸發(fā)INOUTDCLKQnQn+10X01