1
00:00:07,220 --> 00:00:09,290
[Powered by Google Translate] Nate HARDISON: Katika video ya binary, sisi kuonyesha jinsi ya

2
00:00:09,290 --> 00:00:12,540
kuwakilisha seti ya namba nzima, kutoka sifuri juu ya juu,

3
00:00:12,540 --> 00:00:15,110
kutumia tu tarakimu sifuri na moja.

4
00:00:15,110 --> 00:00:17,890
Katika video hii, sisi ni kwenda kutumia nukuu binary kwa

5
00:00:17,890 --> 00:00:21,160
Nakala kuwakilisha barua, na vile, kama vile.

6
00:00:21,160 --> 00:00:22,810
>> Kwa nini sisi bother kufanya hili?

7
00:00:22,810 --> 00:00:25,450
Naam, chini ya Hood, kompyuta kweli tu

8
00:00:25,450 --> 00:00:29,070
anaelewa zeros na ndio, tarakimu binary, tangu hizi

9
00:00:29,070 --> 00:00:32,100
inaweza kuwakilishwa kwa urahisi na mambo ya sumakuumeme.

10
00:00:32,100 --> 00:00:35,040
>> Kwa mfano, nadhani ya kumbukumbu ya kompyuta yako kama muda mrefu

11
00:00:35,040 --> 00:00:37,810
kamba ya balbu mwanga, ambapo kila mtu binafsi bulb

12
00:00:37,810 --> 00:00:40,680
inawakilisha sifuri kama ni akageuka mbali, na moja

13
00:00:40,680 --> 00:00:42,230
kama ni akageuka juu.

14
00:00:42,230 --> 00:00:44,730
Badala ya kutumia rundo la balbu mwanga, baadhi ya kisasa

15
00:00:44,730 --> 00:00:46,990
kumbukumbu gani hii kwa kutumia capacitors kwamba kushikilia chini

16
00:00:46,990 --> 00:00:49,120
malipo kuwakilisha sifuri na malipo high

17
00:00:49,120 --> 00:00:50,780
kuwakilisha moja.

18
00:00:50,780 --> 00:00:52,510
>> Kuna mbinu nyingine pia.

19
00:00:52,510 --> 00:00:55,500
Anyway, ili kuhifadhi chochote katika kumbukumbu, tunahitaji

20
00:00:55,500 --> 00:00:57,590
kwanza kubadili kwenye kitu ambacho inaweza kuwa kweli

21
00:00:57,590 --> 00:01:00,140
kuwakilishwa katika vifaa kimwili.

22
00:01:00,140 --> 00:01:02,450
Basi hebu fikiria jinsi sisi wanaweza kuwakilisha barua kwa

23
00:01:02,450 --> 00:01:04,230
binary nukuu.

24
00:01:04,230 --> 00:01:08,141
Kwa Kiingereza, sisi tumepewa barua 26 katika kialfabeti,

25
00:01:08,141 --> 00:01:12,930
>> B, C, D, na kadhalika, juu kupitia Z. Tunaweza hawawajui kila moja ya

26
00:01:12,930 --> 00:01:16,650
hizi idadi, kusema sifuri kupitia 25, na kisha kwa kutumia

27
00:01:16,650 --> 00:01:18,880
binary nukuu, tunaweza kuwakilisha kila idadi kama

28
00:01:18,880 --> 00:01:20,890
mlolongo wa zeros na ndio.

29
00:01:20,890 --> 00:01:22,420
Hiyo si mbaya sana.

30
00:01:22,420 --> 00:01:25,050
Hata hivyo, si kwamba itakuwa ya kutosha.

31
00:01:25,050 --> 00:01:27,680
Kwa mfumo huu, hatuwezi kutofautisha kati ya

32
00:01:27,680 --> 00:01:29,830
juu na barua lowercase.

33
00:01:29,830 --> 00:01:32,140
Kama tunataka kompyuta yetu ya kuwa na uwezo wa kutofautisha kati ya

34
00:01:32,140 --> 00:01:36,020
kesi mbili, basi tunahitaji ziada namba 26.

35
00:01:36,020 --> 00:01:38,700
Na nini kuhusu vipindi, koma, na

36
00:01:38,700 --> 00:01:40,390
nyingine punctuation alama?

37
00:01:40,390 --> 00:01:43,560
>> Kwenye keyboard yangu, mimi nimepata 32 ya hizo, ikiwa ni pamoja na yote ya

38
00:01:43,560 --> 00:01:46,800
herufi maalum kama caret na ampersand.

39
00:01:46,800 --> 00:01:49,700
Hiyo si ikiwa ni pamoja na wahusika tarakimu, sifuri kupitia tisa,

40
00:01:49,700 --> 00:01:51,840
tangu bado tunataka kuwa na uwezo wa chapa namba katika decimal

41
00:01:51,840 --> 00:01:54,840
nukuu kwenye kompyuta, hata kama kompyuta kweli tu

42
00:01:54,840 --> 00:01:57,830
anaelewa binary nukuu chini ya Hood.

43
00:01:57,830 --> 00:02:00,620
>> Na hatimaye, tutaweza haja ya kuwakilisha tabia nafasi ili

44
00:02:00,620 --> 00:02:02,450
kwamba Space wetu Bar kazi.

45
00:02:02,450 --> 00:02:04,920
Hivyo kuhesabia nje ya jinsi ya kuwakilisha Nakala juu ya kompyuta

46
00:02:04,920 --> 00:02:08,400
inachukua zaidi kidogo kuliko sisi tupate kuwa na mawazo ya awali.

47
00:02:08,400 --> 00:02:11,710
Zaidi ya hayo, kudhani sisi kisha kuja na encoding yetu wenyewe

48
00:02:11,710 --> 00:02:14,560
mpango wa kuwakilisha wahusika kama idadi.

49
00:02:14,560 --> 00:02:17,470
Hata hivyo sisi kuamua encode wahusika inevitably kuwa

50
00:02:17,470 --> 00:02:20,630
kiholela, kama tuliona mapema wakati sisi aliyesema kuhusu kutumia

51
00:02:20,630 --> 00:02:23,730
idadi sifuri kupitia 25 kuwakilisha barua

52
00:02:23,730 --> 00:02:26,850
kupitia Z. Kwa nini matumizi ya 10 kupitia kwa 35 ili tuweze kuokoa

53
00:02:26,850 --> 00:02:29,350
sifuri tisa kupitia kwa wahusika tarakimu?

54
00:02:29,350 --> 00:02:31,590
>> Hakuna sababu ya kweli, sisi tu alichagua chochote walionekana

55
00:02:31,590 --> 00:02:33,770
bora kwa ajili yetu.

56
00:02:33,770 --> 00:02:37,650
Nyuma katika miaka ya 1960 na mapema, hii ilikuwa tatizo halisi.

57
00:02:37,650 --> 00:02:39,370
Tofauti ya kompyuta wazalishaji walikuwa kutumia

58
00:02:39,370 --> 00:02:41,910
tofauti encoding mipango, na hii ya mawasiliano alifanya

59
00:02:41,910 --> 00:02:44,340
kati ya mashine mbalimbali kazi ngumu sana.

60
00:02:44,340 --> 00:02:47,810
Kaskazini ya Taifa ya Viwango Taasisi, ansi,

61
00:02:47,810 --> 00:02:50,210
iliunda kamati ya kuendeleza mpango wa kawaida.

62
00:02:50,210 --> 00:02:53,780
Na mwaka 1963, American Standard Kanuni kwa Taarifa

63
00:02:53,780 --> 00:02:58,600
Interchange, zaidi inajulikana kama ASCII, alizaliwa.

64
00:02:58,600 --> 00:03:01,360
>> ASCII ilitengenezwa kama encoding saba-bit, ambayo

65
00:03:01,360 --> 00:03:03,800
ina maana kwamba tabia ya kila ni kuwakilishwa na mchanganyiko

66
00:03:03,800 --> 00:03:06,070
ya saba zeros na ndio.

67
00:03:06,070 --> 00:03:09,670
Pamoja na wale wawili maadili inawezekana, zero au moja, kwa kila

68
00:03:09,670 --> 00:03:14,040
bits saba, kuna mambo mawili ya saba au 128

69
00:03:14,040 --> 00:03:16,120
wahusika ambayo yanaweza kuwakilishwa na ASCII

70
00:03:16,120 --> 00:03:18,140
usimbaji mpango.

71
00:03:18,140 --> 00:03:21,480
Hivyo 128 wahusika inaonekana kama mengi, haki?

72
00:03:21,480 --> 00:03:24,180
Naam, kumbuka kwamba kuna barua lowercase 26 katika

73
00:03:24,180 --> 00:03:29,260
Kiingereza, mwingine 26 uppercase herufi, tarakimu 10 wahusika,

74
00:03:29,260 --> 00:03:31,470
32 punctuation na herufi maalum,

75
00:03:31,470 --> 00:03:33,430
na moja nafasi tabia.

76
00:03:33,430 --> 00:03:37,050
>> Hiyo inatuweka katika 95, hivyo tuna wahusika mwingine 33 kwamba sisi

77
00:03:37,050 --> 00:03:38,400
wanaweza kuwakilisha.

78
00:03:38,400 --> 00:03:39,900
>> Basi nini kushoto?

79
00:03:39,900 --> 00:03:43,130
Naam, katika siku za maendeleo ya ASCII, teletype

80
00:03:43,130 --> 00:03:45,080
mashine, ambayo ni typewriters ambazo hutumika

81
00:03:45,080 --> 00:03:48,040
kutuma ujumbe katika mtandao, walikuwa kuenea.

82
00:03:48,040 --> 00:03:50,030
Na mashine hizi alikuwa wahusika ziada kutumika kwa

83
00:03:50,030 --> 00:03:52,890
kuwadhibiti, kwa mfano, kuwaambia wakati hoja

84
00:03:52,890 --> 00:03:57,620
magazeti ya kichwa chini ya mstari, malisho ya mstari au ufunguo mpya line,

85
00:03:57,620 --> 00:04:00,440
wakati hoja kwa margin kushoto, kurudi carriage,

86
00:04:00,440 --> 00:04:04,890
au tu kurudi muhimu, na wakati wa kurudi nyuma moja nafasi,

87
00:04:04,890 --> 00:04:07,760
backspace tabia, na kadhalika.

88
00:04:07,760 --> 00:04:10,250
>> Wahusika hawa wanaitwa kudhibiti wahusika, na wao

89
00:04:10,250 --> 00:04:12,680
kuunganika mapumziko ya kuweka ASCII.

90
00:04:12,680 --> 00:04:15,230
Hivyo kama sisi kuangalia meza ASCII, tunaona kwamba kwanza

91
00:04:15,230 --> 00:04:18,800
Idadi 32, sifuri kupitia 31, ni akiba kwa ajili ya kudhibiti

92
00:04:18,800 --> 00:04:20,200
wahusika.

93
00:04:20,200 --> 00:04:23,420
Lakini sisi tu alisema kuwa kulikuwa na 33 kudhibiti wahusika.

94
00:04:23,420 --> 00:04:24,780
Nini mpango huo?

95
00:04:24,780 --> 00:04:29,350
Naam, idadi sifuri na 127, ya kwanza na ya mwisho ya

96
00:04:29,350 --> 00:04:32,560
ASCII kuweka, na mwelekeo kidogo maalum, zeros zote na

97
00:04:32,560 --> 00:04:34,710
ndio, kwa mtiririko huo.

98
00:04:34,710 --> 00:04:36,860
>> wabunifu wa ASCII aliamua, kwa hiyo, kwa

99
00:04:36,860 --> 00:04:39,610
kuhifadhi namba hizi kwa herufi za ziada maalum,

100
00:04:39,610 --> 00:04:43,310
yaani tabia null na tabia DEL.

101
00:04:43,310 --> 00:04:46,340
Null na DEL walikuwa lengo kwa uhariri karatasi mkanda, ambayo hutumiwa

102
00:04:46,340 --> 00:04:48,930
kuwa ni njia ya kawaida ya data hifadhi.

103
00:04:48,930 --> 00:04:51,850
Karatasi mkanda ilikuwa literally tu strip ya muda mrefu ya karatasi, na katika

104
00:04:51,850 --> 00:04:53,760
mara kwa mara vipindi juu ya mkanda, wewe d Punch

105
00:04:53,760 --> 00:04:55,430
mashimo ya kuhifadhi data.

106
00:04:55,430 --> 00:04:58,720
Kutegemea upana wa mkanda, kila safu itakuwa

107
00:04:58,720 --> 00:05:03,186
uwezo wa kubeba tano, sita, saba, nane au bits.

108
00:05:03,186 --> 00:05:05,930
>> Kuwakilisha bit sifuri, wewe d kufanya chochote mkanda, wewe d

109
00:05:05,930 --> 00:05:07,930
tu kuacha nafasi tupu.

110
00:05:07,930 --> 00:05:10,560
Kwa kidogo moja, wewe d Punch shimo.

111
00:05:10,560 --> 00:05:12,980
tabia null ingekuwa kuondoka tu safu tupu,

112
00:05:12,980 --> 00:05:14,480
ikionyesha zeros wote.

113
00:05:14,480 --> 00:05:17,250
Na tabia DEL ingekuwa Punch safu kamili ya mashimo

114
00:05:17,250 --> 00:05:18,550
kupitia mkanda yako.

115
00:05:18,550 --> 00:05:21,300
Kama matokeo, unaweza kutumia tabia DEL kufuta

116
00:05:21,300 --> 00:05:22,440
habari.

117
00:05:22,440 --> 00:05:25,060
Fikiria kuchukua kujazwa-out uchaguzi kura na kisha

118
00:05:25,060 --> 00:05:27,180
kuchomwa mashimo yote unpunched.

119
00:05:27,180 --> 00:05:29,410
>> Wewe kubatilisha kura kwa sababu ni vigumu

120
00:05:29,410 --> 00:05:31,820
kuwaambia nini kura ya awali walikuwa.

121
00:05:31,820 --> 00:05:34,720
Wakati tabia DEL bado kutumika ni ya kisasa

122
00:05:34,720 --> 00:05:37,980
Futa muhimu, tabia null alikuja kutumika kama

123
00:05:37,980 --> 00:05:40,010
ukomeshaji tabia kwa masharti C na

124
00:05:40,010 --> 00:05:41,990
baadhi nyingine data format.

125
00:05:41,990 --> 00:05:45,140
Unaweza kujua ni kama tabia sifuri backslash,

126
00:05:45,140 --> 00:05:47,720
tangu kwamba ni jinsi gani sisi kuwakilisha kwa maandishi.

127
00:05:47,720 --> 00:05:49,580
Hivyo nyuma ya meza yetu ASCII.

128
00:05:49,580 --> 00:05:52,770
Baada ya kwanza 32 kudhibiti wahusika kuja 95

129
00:05:52,770 --> 00:05:54,280
printable wahusika.

130
00:05:54,280 --> 00:05:55,800
>> Kuna wanandoa baridi kubuni maamuzi yenye thamani ya

131
00:05:55,800 --> 00:05:57,330
kuzungumza kuhusu hapa.

132
00:05:57,330 --> 00:06:00,810
Kwanza, decimal tarakimu wahusika, sifuri kupitia tisa,

133
00:06:00,810 --> 00:06:04,050
yanahusiana na idadi 48 kupitia 57, ambayo inaonekana

134
00:06:04,050 --> 00:06:06,980
mpaka unremarkable sisi kuangalia idadi 48 kupitia 57

135
00:06:06,980 --> 00:06:09,080
Imeandikwa katika nukuu binary.

136
00:06:09,080 --> 00:06:11,530
Kama sisi kufanya hivyo, basi tunaona kwamba tabia ya tarakimu,

137
00:06:11,530 --> 00:06:22,320
sifuri, sambamba na 0110000, ramani moja kwa 0110001, wawili kwa

138
00:06:22,320 --> 00:06:26,640
0110010, na kadhalika.

139
00:06:26,640 --> 00:06:27,950
Kuona ruwaza?

140
00:06:27,950 --> 00:06:30,170
Tabia ya kila tarakimu ni mapped kwa sambamba yake

141
00:06:30,170 --> 00:06:35,170
sawa katika nukuu binary, prefixed na 011.

142
00:06:35,170 --> 00:06:38,820
Up Ifwatayo, utaona kwamba barua uppercase kuanza saa 65,

143
00:06:38,820 --> 00:06:41,310
kwa uppercase A, lakini barua lowercase

144
00:06:41,310 --> 00:06:43,010
si kuanza mpaka 97.

145
00:06:43,010 --> 00:06:45,580
Hivyo kuna nafasi 32 kati.

146
00:06:45,580 --> 00:06:47,000
Hiyo inaonekana weird.

147
00:06:47,000 --> 00:06:49,500
Wao ni barua tu 26 katika alfabeti.

148
00:06:49,500 --> 00:06:51,410
>> Mbona kupasuliwa yao juu kama hii?

149
00:06:51,410 --> 00:06:53,960
Tena, kama tunaangalia uwakilishi binary, tunaweza

150
00:06:53,960 --> 00:06:55,230
kuona mfano.

151
00:06:55,230 --> 00:07:01,360
Uppercase ni kuwakilishwa na 1000001, na Herufi za chini ni

152
00:07:01,360 --> 00:07:05,810
kuwakilishwa na 1,100,001.

153
00:07:05,810 --> 00:07:12,770
B uppercase ni kuwakilishwa na 1000010, na b lowercase ni

154
00:07:12,770 --> 00:07:17,280
kuwakilishwa na 1,100,010.

155
00:07:17,280 --> 00:07:19,440
Je, unaweza kuwaambia nini kinaendelea hapa?

156
00:07:19,440 --> 00:07:22,470
kidogo kwamba pili kutoka kushoto, katika wawili

157
00:07:22,470 --> 00:07:26,510
fifths, kwa nafasi 32ths, ni 0 kwa wote wa uppercase

158
00:07:26,510 --> 00:07:30,120
barua, na 1 kwa wote wa barua lowercase.

159
00:07:30,120 --> 00:07:33,130
>> Hiyo ina maana kuwabadili kutoka kwa uppercase Herufi za chini, na

160
00:07:33,130 --> 00:07:36,000
kinyume chake, ni suala la flip rahisi kidogo.

161
00:07:36,000 --> 00:07:38,380
Hivyo kwamba inatuleta hadi mwisho wa meza ASCII.

162
00:07:38,380 --> 00:07:40,700
Je, unaweza kufikiria chochote tumesahau?

163
00:07:40,700 --> 00:07:42,510
Naam, nini kuhusu Enye Kihispania, au

164
00:07:42,510 --> 00:07:44,630
Kigiriki au alphabets Kicyrillic?

165
00:07:44,630 --> 00:07:46,610
Na vipi kuhusu Kichina wahusika?

166
00:07:46,610 --> 00:07:49,050
Kuna mengi ambayo imekuwa kushoto nje ya ASCII.

167
00:07:49,050 --> 00:07:51,920
Hata hivyo, kiwango mwingine aitwaye Unicode imekuwa

168
00:07:51,920 --> 00:07:53,040
maendeleo kwa cover yote haya

169
00:07:53,040 --> 00:07:54,840
wahusika na wengi zaidi.

170
00:07:54,840 --> 00:07:57,040
>> Lakini hiyo ni somo kwa wakati mwingine.

171
00:07:57,040 --> 00:07:58,500
Jina langu ni Nate Hardison.

172
00:07:58,500 --> 00:08:00,650
Hii ni CS50.