???(multiplexers)????????????????????????

1
?????????
2
???

• ???(multiplexers)????????????????????????

3
???

• 16?1????????????????????,????????(data
  selector)?
• Ex. ABCD0000?YD0ABCD1111?YD15

4
???

• ?????OR??NOR,?????????????????
• 74150-TTL???

• ??(strobe)?????????(enable)???(disable)?
• Ex. ABCD0111

5
???

• Ex. 4-1 pp.193X?????STROBE?L?000000010010010
  001010110100010011010

• Ex. 4-2 pp.193

6
?????

• ??????????????????????
• ????????74150??????

7
4?????

• ??????4???????,???4?????(nibble multiplexer)?

8
4?????

• 74157 IC

Active low!!
9
????

• ????(demultiplexer)?????????????????????

• 1?16????ABCD0000 ? Y0DABCD1111 ? Y15D

10
????

• 74154 IC
• DATA?????????????74154???????

11
????

• Ex. 4-3 pp.198

12
4?16???

• ???(decoder)????????????????,??????????ABCD?
• ???4?16???(4-of-16 decoder),?????????????(binary-t
  o-decimal decoder)?ABCD0001 ? Y1H,
  OthersLABCD0100 ? Y4H, OthersL

13
4?16???

• 74154 IC ?????????,????????-?????
• ?74154?DATA??STROBE???????????
• ??????,?????????,????????ABCD0111 ? Y7L,
  OthersH

14
5?32???

• Ex. 4-4 pp.201????(chip expansion)XL
  ????,????XH ????,???? XABCD00011 ? ??Y3L,
  OthersHXABCD10011 ? ??Y3L, OthersH

15
BCD???????

• BCD?(binary-coded decimal)???????????????4???
• BCD??4?????,?0000?1001,??1010?1111???9,?????BCD???

16
BCD???????

• 4?10???BCD???????ABCD0011? Y3H,
  OthersLABCD1000? Y8H, OthersL

17
BCD???????

• 7445 IC

18
BCD???????

• Ex. 4-5 pp.206
• Ex. 4-6 pp.206a. ABCD0101b. ABCD1001c.
  ABCD1100

19
??????

• LED?????????????
• ??????????????????7?LED???0-9????
• ????????LED???????????

• ??????????????LED?VCC???

20
??????

• 7446 IC????????,????????????
• 7446????????
• ????????4?????(BCD??)?7?????(a?g?)?ABCD0111???
  ??7

21
??????

• 7448 IC????????,????????????
• 7448???????

22
???

• ???BCD???

• ???(encoder)??????????????????????

• ???5? ABCD0101

23
???

• 74147 IC????BCD???X9L? ABCDLHHL
  9???X7L? ABCDHLLL
  7???
• 7417????????(priority encoder)-?????????????????X
  9?X0

24
???

• Ex. 4-7 pp.2146???? ABCDHLLH

25
????, XOR

• ????(eXclusive-OR gate, XOR)
• ???????????,????????
• 2????????2?????????????

26
????, XOR

• ???XOR?

???????????,????????
27
????, XOR

• ???XOR?

???????????,????????
28
?????????

• ???(even parity)n?????????1? ?110011, 1111
  0000 1111 0011???(odd parity)
  n?????????1? ?110001, 1111 0000 1111 0111
• ?????(parity checker)-??XOR?

• ??????????
• ??????????

29
?????????

• ?????(parity generator)??????,??????????????????,
  ??????????????????????? X7X6X5X4X3X2X1X0
  01000 0001? X81
• ????????,??????

30
?????????

• ??????????????????????? ?? 0100
  0011 ??????? 0 0100 0011 ????????????????
  O.K. ???? error
• 74180 IC

31
?????????

• 74180 IC ???????????????,??????????????????
• Ex. 4-8 pp.223??74180 IC??9????????

32
?????

• ?????(read-only memory, ROM)??????????,???????????
  ?????,?????????????????????
• ???ROM???????????

33
?????

• ?????(on-chip decoding)??????????????
• ?3?8??? ABC100?Y3Y2Y1Y00110
  ABC110?Y3Y2Y1Y00011
• n?????2n?????

34
??ROM

• ?????????????(word)???????????????????????????????
  ?
• ?????32???ROM,??8?4??????,???8X4 ROM???
• ????TTL ROM7488 IC32X8 ? 256??ROM74187
  IC256X4 ? 1024??ROM74S370 IC512X4 ? 2048??ROM
• ????????,???(mask)????????????

35
??????

• ROM????AND-OR???????????

36
??????ROM

• ??????ROM (programmable ROM, PROM)???????????????
• PROM???????(burning in)?????????????????????????
• ??PROM???ROM??????????????????????
• ??X???????(fusible link),???????
• PROM?,AND???????????,?OR??????

37
??????ROM

• ?????????
• ????PROM(EPROM)???????????????,??????????????????
  ?,????????PROM?ROM????????

38
??????????

• PAL (Programmable Array Logic)??????????????????,?
  ??????????
• PAL?????????AND?????????OR???

39
PAL

• ??PROM???,????????,??????????OR????
• ???PAL???????

40
??????????

• PLA (Programmable Logic Array)??????????,??????AND
  ??????OR???
• PROM?PAL?PLA???????????(Programmable Logic
  Device, PLD)?

41
PLA
42
????????

• ?????????????????
• ?????????????,?????????