Sophie: howto-text-ja-9.0-1mdk noarch

howto-text-ja-9.0-1mdk.noarch.rpm

The Clock Mini-HOWTO

Ron Bean

rbean@execpc.com

JF Project - ú{êó

JF@linux.or.jp

v2.1, November 2000

Rs[^É³mÈÔðÝèµÄAvª¶íÈ¢æ¤É·éû@B

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Table of Contents
1. Í¶ßÉ
   
    1.1. ÙñÆÍ½Èñ¾¢H
    1.2. \tgEFAÌüèæF¼ÈA[JCu
    1.3. Ó«
   
2. Linux ÍÇÌæ¤ÉÔðvÁÄ¢éÌ©
   
    2.1. î{IÈdgÝ
    2.2. RtNgÌÂ\«
    2.3. RTC ÉÍ[J^C© UTC ÌÇ¿çðg¤×«©H DST ÁÄ½
        H
    2.4. ^C][ÌÝèÉÂ¢Ä
    2.5. ÇÌöxÌ¸xªKv©
   
3. \tgEFA
   
    3.1. clock(8) Æ hwclock(8)
    3.2. Adjtimex(8)
    3.3. xntpd Æ ntpd - lbg[N^CvgR
    3.4. chrony vO
    3.5. clockspeed vO
   
4. dgv
   
    4.1. CHU ÆuGadget Boxv
    4.2. WWV ÆuMost Accurate Clockv
    4.3. GPS ÆuTotally Accurate Clockv
    4.4. ·g^CVOiF DCF77, MSF(Rugby), WWVB
   
5. ú{êóÉÂ¢Ä

1. Í¶ßÉ

1.1. ÙñÆÍ½Èñ¾¢H

PC }U[{[hãÌA^CNbN (Real-Time-Clock, RTC) `bvÌ
s³m³ÍL¼Å·B½¢Ä¢·¬½èx·¬½è·éÌÅAúµ¸Â
vª¶ÁÄ¢«Ü· [1]Bµ©µALinux ÉÍ\tgEFAãÅ±êðC³
·éÈPÈû@ª èÜ·B»Ìû@ðg¦ÎAOÌñ\[XÉç¸Æ
àvðñíÉ³mÉÛÂ±ÆªÅ«Ü·B½¾A»ÌÝèû@ðmélª 
Üè¢È¢ÌÍA(¨»ç) ÈºÌæ¤ÈRª é©ç¾ÆvíêÜ·B

 

 E Linux ÌÝèSÊððàµ½¶ÅÍÙÆñÇ±êÉGêçêÄ¨ç¸A
    (OÌñ\[Xðp·éêÈOÍ) ©®IÉÝè³êé±ÆàÈ¢
    ÌÅAftHgÅÍp³êÈ¢±ÆB
   
 E man clock ÆR}hðÅÂÆ clock (3) ª\¦³êÜ·ªA±êÉÍS
    RÊÌ¿ªLÚ³êÄ¢é±ÆBman 8 clock àµÍ man 8 hwclock
    ðµÄ¾³¢ (ZNVðwè¹¸É man page ðõµ½êA
    êÊÌfBXgr[VÅÍZNVÌá¢ûªæÉ\¦³êé
    æ¤ÉÈÁÄ¢Ü·B/etc/man.config Åwèµ½Éõ·éfBXg
    r[Và èÜ·)B
   
 E »à»àÔ©ÌðCÉµÄ¢È¢lª½¢çµ¢±ÆB
   
 E vÌÔðCÉ·éÐÆÍAlbg[N^CT[o (netwok time
    server) âdgv (radio clock) Æ¢Á½OÌñ\[XÉVXe
    NbNð¯ú (sync) ³¹Ä¢élªå¼Å é±ÆB±ÌêARTC
    ª³m©Ç¤©Í(ÙÆñÇ) ÖWªÈÈèÜ·B
   
 

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vÍñíÉ³mÉÈèÜ·)BÜ½AàÁÆôû³ê½û@ÅÔ²®µ½¢
lÌ½ßÉAeíÌîñ¹àÐîµÄ¢Ü·BãÒÌêA»ÌèÌ¶Ìð
àÍ¨¨ÞËµÁ©èµÄ¢éÌÅA{ÅÍÚðµÜ¹ñB

{ÌOo[WÅÍAÃ¢VXeð¢ÜàgÁÄ¢élÌ½ßÉ®Ì 
clock (8) vOÉÂ¢ÄÚµà¾µÄ¢Üµ½ªA¡ñÍ»ÌZNV
ðÈªµÜµ½B»Ý½ÌfBXgr[Vª clock (8) É©¦
Ä hwclock (8) ðÌpµÄ¨èAhwclock (8) vOÉÖ·é¶£Ìûª
¸ÁÆDêÄ¢é©çÅ·Bclock (8) Ìðà¶ªKvÈêÍAÒÉ[
Åmç¹Ä¾³¢B½¾A»ÌêÍAæ¸ hwclock (8) ÉÂ¢ÄÌÍð
ÇñÅ©çÉµÄ¾³¢B

    Ó: RTC âVXeNbNðC³·évOðÀs·éÉÍ
    "root" ÅOCµÈ¯êÎÈèÜ¹ñB±Ì¶Åq×évOÌ
    å¼ÍAroot  ÀªKvÅ·Bi©çOtBJC^[tFCXµ
    ©gÁÄ¢È¢êÍAî{IÈ UNIX ÌVFR}hð¢Â©wÔ
    Kvª é©àµêÜ¹ñB
   
    Ó: }VãÅ¡Ì OS ðgÁÄ¢éêÍA»Ì¤¿ÐÆÂ¾¯Å
    RTC ÌÝèðs¢A¼Ì OS ÆÌÔÅÔªH¢á¤±ÆªÈ¢æ¤É·
    éKvª èÜ·B½¾ANÉ 2 xÌÄÔÌ²®ÉÂ¢ÄÍÊÅ· (Ú
    µÍA DST ÌZNVð²¾³¢)B
   
fAu[gVXeÅåÉ Windows ðgÁÄ¢éÈçALinux ÅÅÍÈ
AWindows ÅÌNbN\tgEFAÉÂ¢Ä²×½¢Æv¤©àµêÜ¹ñ
B»ÌêÍAÌ NTP EFuTCgÌà¾ð²¾³¢Bhttp://
www.eecis.udel.edu/~ntp/software.htmlB{ÅÌdgvÌà¾Ì½ÍA
Windows p\tgEFAÉÖ·éàÌàÜÜêÄ¢Ü·B

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1.2. \tgEFAÌüèæF¼ÈA[JCu

{ÅÍ\tgEFAð_E[hÅ«éêÆµÄ¢Â©ÌTCgð
°Üµ½ªACD-ROM ÅªèÉüçÈ¢êÍ Linux VXeSÌð»±©ç
_E[h·é±ÆàÅ«Ü·BÌÍA»Ìæ¤ÈTCgÍ
sunsite.unc.edu Ì ftp A[JCuÆeÌ»Ì~[TCgÅ éÆêª
ÜÁÄ¢Üµ½ªA»Ý sunsite Í http://metalab.unc.edu/linux/ Æü
¼³êÄ¢Ü· (óF 2001N10»ÝÅÍ ibiblio http://
www.ibiblio.org/pub/linux/ Æ¢¤¼ÌÉÏX³êÄ¢Ü·)BfBXgr
[VÌÉÍÆ©ÌEFuTCgðÁÄ¢éàÌà èA»ÌÈ©É
Í±Ì¶Åµ¤\tgEFAªÜÜêÄ¢éêà èÜ·B

ÅßÅÍ Linux ð CD Åüè·élªÙÆñÇÅ èA»¤µ½ CD ÉÍft
HgÅCXg[³êÈ¢æ¤Èeí\tgEFAà½¢Ä¢ÜÜêÄ¢
éÌÅA©ªÅÍÓ¯µÄ¢ÈÆà{Åq×évOªùÉè³É 
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Å· (ãqµ½ metalab TCg©çàüèªÂ\Å·)BÃ¢Nðwèµ
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1.3. Ó«

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2. Linux ÍÇÌæ¤ÉÔðvÁÄ¢éÌ©

2.1. î{IÈdgÝ

Linux VXeÉÍ 2 íÞÌvª èÜ·BÐÆÂÍAobe[ì®Ì
A^CNbN(RTC â CMOS NbNàµÍn[hEFANbNÆà
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(System Clock, J[lNbNàµÍ\tgEFANbNÆàÄÎêÜ
·) Å èA±êÍ^C}èÝÉîÃ\tgEFAEJE^(software
counter)Å·BVXeNbNÍVXeÌÒÈOÉÍ¶ÝµÈ¢ÌÅ
AN®É RTC (àµÍ»êÈOÌOv) ÉæÁÄú»³êéKvª
 èÜ·Bntpd Ìt®¶ÅuNbNvðQÆ·éÆ¢¤êARTC ÅÍÈ
VXeNbNÌQÆðÓ¡µÄ¢Ü·B

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mÉÛÂãÅÅàÈPÈû@ÍAÔªYéðvZµÄ\tgEFAã
Å»êðC³·é±ÆÅ·BRTC ÍVXeÌÒµÄ¢È¢¾¯gp³ê
éàÌÈÌÅARTC ÌC³ÍAN®ÉðÇÝÞÛÉ clock(8) © 
hwclock(8) ðgÁÄs¢Ü·BVXeNbNÌC³ÍA^C}èÝÉ
æèVXeÔªiÞÛÉ adjtimex(8) ðgÁÄYðC³·é±ÆÉæè
À{µÜ·B

adjtimex(8) ÌãíèÉ cron ðgÁÄ clock(8) © hwclock(8) ðèúIÉ
ÀsµAVXeNbNð(³mÉ²®µ½)RTC É¯ú³¹éÆ¢¤û@à
È¢í¯ÅÍ èÜ¹ñB±êÍ clock(8) Ì}jAy[WÅ§³êÄ
¢Ü·µA éöxpÉÉ¯ú³¹é±ÆÅ¼ÒÌÔÌYð¬³µÄV
XeNbNÌªåÉuWvv·é±ÆªÈ¯êÎâèÈ@\
µÜ·ªAadjtimex(8) ðgÁÄ²®µ½ûªGKgÅ·BAvP[V
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N^CT[oâdgv©çèúIÉÔðÇÝñÅp±IÉVXeN
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vðð¯éû@à èÜ·BàµN®ÉK¸lbg[NRlNVð£
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2.2. RtNgÌÂ\«

ntpd Ìæ¤ÈvOðgÁÄ¢éÈçARTC ð (²®ÏÝÌ)VXeN
bNÉ¯ú³¹æ¤Æv¤©àµêÜ¹ñBµ©µA±êÍVXeªª
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2.3. RTC ÉÍ[J^C© UTC ÌÇ¿çðg¤×«©H DST ÁÄ½H

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êAÁÉ¿µ¢±ÆÅÍ èÜ¹ñ)ADST ªâèÉÈéêÅàVXeN
bNÍ¸ÁÆ³mÈÔð`¦Ä¢éÌÅARTC ª¶Á½ÆµÄà½à
Ct©È¢Åµå¤Bµ©µA¢Âu[gð·é©Æ¢¤±ÆÍ\ß\ªª
t©È¢ÌÅA[J^CðKvÆ·é OS ðgÁÄ¢È¢êÍA RTC
ð UTC ÉÝèµ½ûª¢¢Åµå¤B

Dallas Semiconductor Ì RTC `bv (±êÍAMotorola `bvÌãíèÉ
IBM AT @â»ÌÝ·@ÉÚ³êéæ¤ÉÈÁ½`bvÅ·) ÍAÀÛÉ`b
v©ÌÉ UTC ð DST ÉÏ··é\ÍªõíÁÄ¢Ü·ªAÏX·×«útª
 ç©¶ßn[hIÉÅè³êÄ¢Ä»êð\tgIÉÏ¦é±ÆªÅ«È¢
ÌÅA±Ì@\ÍgíêÄ¢Ü¹ñBÅVÌo[WXVª 2000N4Ìæ
êújúÆ 10ÌÅIújúÉÀ{³êÜµ½ªA»êÈOÌo[WÌ`
bvÅÍA»ê¼êÙÈÁ½úªgíêÄ¢Ü·B (Ü½A±êÍ(O
Æ)á¤útðgÁÄ¢éÅÍA¾ç©É@\µÜ¹ñB) ³çÉARTC Í
(PÌÌ`bvÅÍÈ) }U[{[hÌ`bvZbgÌÉgÝÜêÄ¢é
êà½ÈÁÄ¢éÌÅA»êç·×Äª±Ì\ÍðÁÄ¢é©Ç¤©
ÒÉÍª©èÜ¹ñB

ªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªª

2.4. ^C][ÌÝèÉÂ¢Ä

¨»ç Linux CXg[ÌÛÉAÇÒÍ^C][ð³µÝèµÄ¢
éÆv¢Ü·Bµ©µAàµ½ç©ÌRÅ»êðÏXµÈ¯êÎÈçÈ¢ê
AàµÍ DST ÉÖ·é©Ì@¥ªÏX³ê½ê(±¤¢¤@¥ÏXª
pÉÉN±éà èÜ·)A^C][ðÏX·éû@ðméKvª¶¶é
Åµå¤BVXeÔª«Á©èÔ¸êÄ¢éæ¤ÈÆ«ÍA^C]
[ (àµÍADST) ÌÝèÉâèª èÜ·B

^C][â DST ÌîñÍA/usr/share/zoneinfo (àµÍ /usr/lib/
zoneinfo) ÉÛ¶³êÄ¢Ü·B[JÈ^C][ÍA/etc/localtime
©çãLÌt@CQÌÐÆÂÉV{bNNð£é±ÆÅè³êÄ
¢Ü·B^C][ðÏX·éÉÍA»ÌNð£èÖ¦Üµå¤Bàµ
DST ÌútªÏíçÈ¢êÍA»Ìt@CðÒW·éKvª èÜ·B

Ü½AÂ«Ï TZ ðgÁÄ»ÝÌ^C][ðÏX·é±ÆàÅ«Ü·B
±êÍÙÈé^C][É éu}VÉOCµÄ¢éêÉÍAÖ
Èû@Å·BÚµÍAtzset Æ tzfile Ì}jAy[Wð²¾³
¢B

±êÉÂ¢ÄÍAÌTCgÅª©èÕà¾³êÄ¢Ü·B http://
www.linuxsa.org.au/tips/time.html

ªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªª

2.5. ÇÌöxÌ¸xªKv©

~bPÊÅÌ³m³ªsvÈçAhwclock(8) Æ adjtimex(8) ¾¯Å¨»ç
[ªÅ·B^CT[oâdgvÉ²ÉÈÁ½ÆµÄà³Í èÜ
¹ñªAÒÍÃ¢ clock(8) vO¾¯Å±±N·Îçµ¢Êð¾
Ä¢Ü·B¼ûALAN ãÉ¡Ì}Vª éêÍAÝ¢Évð©®IÉ
¯ú³¹é±ÆªÅ«êÎÖÅ·( é¢ÍA»êªsÂÈêà èÜ
·)B»êÈOÉàAÁÉKvªÈÄàgÁÄÝÄÊ¢c[Þà èÜ·
B

Linux ¾¯µ©ç¹È¢}VÈçÎARTC ð UTC (àµÍ GMT) ÉÝè
µÜµå¤BRTC ð[J^CÉÝè·éKvÌ éfAu[gVX
eÌêÍAÓ·×«_ª èÜ·BàµÄÔÌÏXOãÉ Linux ð
u[gµÈ¯êÎÈçÈ¢Æ«ÍAvªbèIÉêÔ¸êÄµÜ¤±Æª
 éÆ¢¤±ÆÅ·B»ÌóÔÍAà¤êÂÌ OS ðN®·éÜÅ±±ÆÉ
ÈèÜ·B3 ÂÈãÌ OS ªÚÁÄ¢éêÍA»Ì¤¿ÐÆÂÌ OS ¾¯Å
DST ð²®·éæ¤Cðt¯Ä¾³¢B

ªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªª

3. \tgEFA

3.1. clock(8) Æ hwclock(8)

ÇÌæ¤ÈfBXgr[VÅàÃ¢ clock(8) ©Vµ¢ hwclock(8)
ÌÇ¿ç©ÍCXg[³êÜ· ( ÔÌ²®Í©ªÅ·éKvª èÜ
·)Badjtimex(8) àCXg[³êé©AIvVÆµÄ CD É¯«³ê
Ä¢éÅµå¤ (adjtimex ÍÊíÌ Linux A[JCuTCg©ç_E[
h·é±ÆàÅ«Ü·)BfBXgr[VÉæÁÄÍ X Window ãÅO
tBJÉNbNðÝè·évOðÜñÅ¢½èµÜ·ªA»êç
Í ÜÅC^NeBuÈg¢ûð·éæ¤ÉÈÁÄ¢éÌÅ (©®Ýè
ªÅ«È¢ÌÅ)Aclock(8) â hwclock(8) àCXg[³êú»XN
vgÅ©®Ýèªoéæ¤ÉÈÁÄ¢Ü·B

clock ÌêAÔ²®Ì½ßÌlÍè®ÅvZµÈ¯êÎÈèÜ¹ñB¼
û hwclock ÌêA»ÌR}hðgÁÄ RTC ðZbg·é½Ñ²ÆÉ²
®¦ð©®ÅvZµÄêÜ· (¼ûððÝÉgÁÄ RTC ðÝè·éÆÔ²
®ª¶ÁÄµÜ¤ÌÅA²®ÌÛÍK¸Ç¿ç©êûðg¤æ¤ÉµÄ¾³
¢)Bàµ clock µ©üÁÄ¢È¢Ã¢VXeðgÁÄ¢ÄAbvO[h
µ½¢êÍA hwclock Í util-linux pbP[WÌo[W 2.7 È~É
ÜÜêÄ¢Ü·BÚµÍ}jAy[Wð²¾³¢B

    Note: hwclock(8) Ì}jAy[WÍAºÊÝ·«ðÛÂ½ßÉ clock
    ÌR}h¼ÅÄÑo·ÝèÉÈÁÄ¢é±Æª éÌÅA¼ûÌR}
    h¼ðµÄ¾³¢Bhwclock Í clock pÌR}hÉà½ÍµÜ·
    ªA»ÌêÊÍ clock ÌÆÍÙÈé©àµêÜ¹ñBÁÉ 
    hwclock -a ÍAclock -a ÆÍ©ÈèÙÈÁÄ¢Ü·Bàµ hwclock ÉA
    bvO[hµÄ¢éÈçAú»XNvgàÅ clock pR}hðg
    ÁÄ¢éªÍ·×Ä hwclock ÌlCeBuR}hÉ·µÖ¦é±Æð
    ¨··ßµÜ·B
   
ú»XNvgÍfBXgr[V²ÆÉÙÈéÌÅA½²×È¢
ÆNbNðÝèµÄ¢éêª©Â©çÈ¢©àµêÜ¹ñBT^IÈê
Í /etc/rc.local â /etc/rc.d/rc.sysinitA/etc/rc.d/boot ÈÇÅ·B

RTC ÌÔ²®pÌlÍA/etc/adjtime ÉÛ¶³êÄ¢Ü·BRed Hat Ìê
 etc/sysconfig/clock ÉXNvgª èA»ÌXNvgÅ hwclock Ì
IvVð§äµÄ¢Ü·B

NbNÌÝèÅvÌK¥IÈYð²®·éêÍAdbÅÌñª³m
ÅÍÈ¢êª è¾é±ÆðOªÉu¢Ä¾³¢ (óFÜ AAJ
ÅÌb¾Æv¢Ü·)BZgWIâ GPS V[oðÁÄ¢È¢Æ«ÍA
(303)499-7111 ÉdbðµÄA WWV ©çñð·±ÆàÅ«Ü·(±êÍA
RhÌ{_[ÖÌ·£dbÉÈèÜ·)B3 ªÅ©®IÉØêÜ·ªA
NbNÌÝèÉÍ[ªÅ·BUSNO âJi_Ì CHU àñT[rXðµÄ¢
Ü·ªAÒÍ WWV ÌÙ¤ª¢¢Æv¢Ü·BÔÌAiEXÆñ¹ÌÔ
uª·¢©çÅ·B¼Éà ntpd t®Ì ntpdate ðgÁÄlbg[N^C
T[o©çð¾é±ÆàÅ«Ü·µA www.time.gov <http://
www.time.gov/> ÉÍ javaclock à èÜ·B

ÇêðgÁ½êÅàÝè·éÌÍVXeNbNÅ èARTC ÅÍ èÜ
¹ñ(date R}hÌ}jAy[Wð©ÄAÇ¤¢¤tH[}bgðg¤
Ì©mFµÄ¾³¢)B»µÄA hwclock ðgpµÄ RTC ðÝèµAK¥I
ÈYÌðvZµÜ·Bè®ÅâéêA1 b© 2 bÈàÌë·ÉÝèµ
ÄAêTÔãÉ¨æ»ÌYÌ¦ðmF·éæ¤ÉµÄ¾³¢B»µÄ 
adjtimex ðÀsµAVXeNbNð²®µÄ¾³¢B

ªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªª

3.2. Adjtimex(8)

adjtimex R}hÍAJ[lÌÔÏÌ²®ªÅ«éÌÅA»êÉæÁÄ
VXeNbNÌXs[hðÏX·éæ¤ÉÈÁÄ¢Ü·(ÀsÌÛÉÍ
root ÅOC·éKvª èÜ·)Bhwclock ÍÝvªGíÅ èAVXe
NbNÆ RTC Ìðär·éÛÉ /etc/adjtime ÉÛ¶³ê½Aclock
Åà hwclock Åàg¦é¯êÌ²®lðg¤æ¤ÉÈÁÄ¢Ü·B»êä¦
RTC ÌK¥IYð¼µÄµÜ¦ÎAVXeNbNð²®·éÌàñíÉ
ÈPÅ·BêUNbNª³µ¢Xs[hÅ®æ¤Éo½ÈçAú»X
NvgÉÝèsðÇÁµÄN®ÉJ[lÏðKØÉÝè·é±ÆªÅ
«Ü·Badjtimex Í clock Åà hwclock Åàg¦éæ¤ÉÝv³êÄ¢éÌ
ÅAOqµ½u11 ª²ÆvÌoOàñðÅ«éæ¤ÉÈÁÄ¢Ü·B

adjtimex ÌCXg[ªÏñ¾çAÝèÉÖ·éÚµ¢îñð¾éÉÍ man
8 adjtimex Æ^Cv·é© (ÝèÈOÌîñÉÖ·é adjtimex Ì}jA
y[Wà èÜ·)A/usr/doc/adjtimex-1.3/README Ì README t@CðÇ
Þ©µÄ¾³¢ (fBNgpXãÌo[WÔÍAadjtimex ÌÅV
o[WÌÔÆÈèÜ·)B

ªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªª

3.3. xntpd Æ ntpd - lbg[N^CvgR

xntpd (NTPv3) ÍAntpd (NTPv4) Éu«·íèÜµ½BÃ¢o[WÍ»Ý
eiXÌÎÛOÆÈÁÄ¢Ü·B

ntpd ÍAlbg[NzµÉvð¯ú³¹éWIÈvOÅ èAv
OÉÍÚ±Â\ÈpubN^CT[oÌXgªt®µÄ¢Ü·B
ÝèÉÂ¢ÄÍ{Åq×Ä¢éæ¤ÈvOæèàââ¡G©àµêÜ
¹ñªA±ÌíÌ¿É»¡ª éÈçÜ¸´ÁÆßÄÝé±Æð¨··ß
µÜ·B

ntpd ÉÖ·éîñÍ NTP ÌEFuTCgÅ é http://www.eecis.udel.edu/
~ntp/ ÉWñ³êÄ¢Ü·BÜ½±±ÉÍAÔÉÖA·élXÈ¿ (¼Ì
OS pÌ\tgEFAàÜÞ) ÖÌNªfÚ³êÄ¢Ü·BfBXgr
[VÉæÁÄÍ ntpd ª CD ÉûßçêÄ¢éêà èÜ·Bpub
N^CT[oÌXgÍA http://www.eecis.udel.edu/~mills/ntp/
clock2.html ð²¾³¢B

ntpd ÌärIVµ¢@\ÉAuo[Xg[h(burst mode)vª èÜ·B±
êÍ_CAAbvÅXµ©C^[lbgÉÚ±µÈ¢}VpÉÝv³
ê½@\Å·B

ntpd ÉÍAdgvphCoà½ÜÜêÄ¢Ü· (½¾AÈ©ÉÍ Ü
è«\ÌÇÈ¢Ìà èÜ·ª)BdgvÌåªÍ¤pÆµÄì¬³êÄ
¢ÄAçhÌliªt¢½èµÜ·ªA»êÉ©íéÀ¿Èèià¶Ýµ
Ü· (±êÉÂ¢ÄÍãÙÇðàµÜ·)BÈOÍÙÆñÇª WWV â WWVB 
V[oÅµ½ªA»ÝÅÍåªª GPS V[oÆÈÁÄ¢Ü·BNIST ÌE
FuTCgÉÍ PDF t@C`®ÅÌdgvÌ»¢³ê\ª èÜ·B 
http://www.boulder.nist.gov/timefreq/links.htm (y[WÌöÅ·)BÜ½
NTP EFuTCgÉàdgvÌ»¢ïÐÖÌNª½fÚ³êÄ¢Ü·
B http://www.eecis.udel.edu/~ntp/hardware.htm ¨æÑ http://
www.eecis.udel.edu/~mills/ntp/refclock.htmBÇ¿çÌXgàAXV
³ê½è³êÈ©Á½èÌæ¤Å· :-)@ ntpd ÌhCoÍA http://
www.eecis.udel.edu/~ntp/ntp_spool/html/refclock.htm É èÜ·B

ntpd ÉÍA_CAAbvpÌ^CT[rXÉÂ¢ÄÌhCoàÜÜêÄ
¢Ü·B±êçÍ·×Ä·£dbðg¤ÌÅAvOðg¤OÉdb¿
àªÇêç¢ÉÈé©vZ·éÌðYêÈ¢Å¾³¢B

ªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªª

3.4. chrony vO

xntpd ÍàÆàÆlbg[N^CT[o©dgvÉíÚ±Å«é}V
pÉìçêÄ¢Üµ½B_IÉÍXµ©Ú±µÈ¢}VÅàg¦éÌ
Å·ªARichard Curnow Ív¢ÊèÌû@Å xntpd ð®©·±ÆªÅ«È©
Á½½ßAchrony Æ¢¤vOðì¬µAISP É_CAAbvÅÚ±·
éÆ«µ©lbg[NÉANZXµÈ¢[Uü¯ÉÊÌèiðñµÄ
êÜµ½ (±êÍ ntpd ªV@\Å é burst mode Åðµæ¤Æµ½ÌÆ
¯¶âèÅ·)Bchrony Ì»ÝÌo[WÉÍA·Ôd¹ðItÉ·é}
VpÉ RTC ÌK¥IYððÁ·é@\àÜÜêÄ¢Ü·B 

Úµ¢îñÍ Richard Curnow ÌEFuTCg http://
www.rrbcurnow.freeuk.com/chrony â http://go.to/chrony ð²º³¢B
chrony ÉÍñÂÌ[OXgª èAÐÆÂÍAiEXpAà¤ÐÆ
ÂÍ[UÉæéc_ÌêÆÈÁÄ¢Ü·BÚµÍ
<hrony-users-subscribe@egroups.com> ©
<chrony-announce-subscribe@egroups.com> É[ðMµÄ¾³¢B

chrony ÍÊí\[XR[hÌÝÌzzÆÈÁÄ¢Ü·ªA Debian ÅÍA
unstable ÌÈ©ÉoCiÅªÜÜêÄ¢Ü·B\[Xt@CÉÂ¢ÄàA
¼È Linux A[JCuTCgÅüèÅ«Ü·B

ªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªª

3.5. clockspeed vO

»êÈOÌIðÆµÄADJ Bernstein Éæé clockspeed Æ¢¤vO
ª èÜ·B±êÍlbg[N^CT[o©çÔðæ¾µÄA3 b²Æ
ÉVXeNbNðÄÝè·éÆ¢¤PÈû@ðg¤àÌÅ·BÜ½ LAN
ãÉ é¢Â©Ì}Vð¯ú³¹é½ßÉg¤±ÆàÅ«Ü·B

ÞÌEFuTCg http://Cr.yp.to/clockspeed.html ÍÆ«Ç«guª 
éæ¤Å·Bàµ DNS G[ªoéæ¤ÈçAÄxúÉANZXµÄÝÄ
¾³¢B±ÌªÉÂ¢ÄÍÚµ¢îñªüèæAXVµÜ·B

ªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªª

4. dgv

4.1. CHU ÆuGadget Boxv

CHU ÆÍAI^ßxÉ éJi_ZgñÇ (Canadian shortwave time
station) Ì±ÆÅ èAOÌ WWV ÉÞµ½gDÅ·ªA¼ÒÉÍÐÆ
Â¾¯dvÈá¢ª èÜ·BCHU ÍpêÆtXêÅñðñ·é¾¯
ÅÈAÃ¢ "Bell 103" (300 baud) fg[ðgÁÄêªÔuÅñð
úµÄ¢éÆ¢¤_Å·B±Ìg[ÍfR[hªñíÉeÕÅ é½ßA
Bill Rossi Íf(fR[_)ðg¤ÜÅàÈAZgWIÆTEhJ[
hÅðÍÅ«é±Æð©µÜµ½BCHU ©çÌMðóMÅ«éÈçA±ê
ÍÅàÀãªèÈdgvÆµÄg¦Ü·BZgÌóMóµÍêúÌ¤¿É½
x©Ï»µÜ·ªABill ÉæéÆAúÉññ (©Æ[û) ügðÏ¦êÎÙ
Ú 24 ÔóMÅ«é»¤Å·BCHU ÌúÍ 3.33, 7.335, ¨æÑ 14.670
MHz Å·B

Ú×Í Bill Rossi ÌEFuTCg http://www.rossi.com/chu/ ð²¾³
¢B\[Xt@CÍ¼ÈA[JCuTCg©çàüèÅ«Ü·B CHU Ì
ñT[rXÉÂ¢ÄÍA http://www.nrc.ca/inms/time/ctse.html ð©Äº³
¢B

uGadget BoxvÆ¢¤vª NTP EFuTCgÉ èÜ·B±êÍÀ¿È
300 baud ÌfÆKÈZgWIðgÁÄ CHU ÌñðfR[h·éÆ
¢¤àÌÅ· http://www.eecis.udel.edu/~ntp/ntp_spool/html/gadget.htmB
±ÌvÅÍêpÌ¼ÊvgîÕÉÖ·é PostScript }ðfÚµÄ¢
Ü·ªAîÕ©ÌÍ©ªÅìçÈ¯êÎÈèÜ¹ñ (àµÍAìÁÄêé
lðT·Kvª èÜ·)B

ntpd ÉÍ CHU V[opÌhCo (type 7) ªÜÜêÄ¢Ü·B±êÍu
Gadget BoxvÌæ¤Èfðg¤©AàµÍ Sun SPARCstation ( é¢Í
»ÌÝ·I[fBIhCoðÁ½}V) Ì}CNüÍÉ¼Ú¹ºðüÍ
·é±ÆÅ®æ¤ÉÈÁÄ¢Ü·B

ªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªª

4.2. WWV ÆuMost Accurate Clockv

Heathkit ÐÌuMost Accurate ClockvÆ¢¤Ìð·¢½±Æª éûà¢é
Åµå¤B±êÍ WWV ÌñðóMµÄfR[hµAIvVÌVA|
[gðgÁÄRs[^ÉÚ±·éÆ¢¤àÌÅ·BHeathkit ÍªÜ¦É
±ÌLbgÌÌð~ßÄµÜ¢Üµ½ªA1995NÜÅÍ±ÌvÌ®¬iÅ
ÌÌð±¯Ä¢Üµ½ (»ÝÍÌµÄ¢Ü¹ñ)B(vÈOÌ»iðÜß
½) Heathkit ÐÖÌmX^WAð¢½y[Wª http://
www.heathkit-museum.com É èÜ·BHeathkit Ð©ÌÍ¡àÝÅ èAw
KpÌ³ÞðÌµÄ¢Ü·BÚµÍ http://www.heathkit.com ð²¾
³¢B

Dave Mills ÉæéÆAHeathkit ÐÌuMost Accurate ClockvÉÖ·éÁÍ
à¤·®úÀØêÉÈéÌÅAàµ©·éÆ»ÌN[ðVO`bv IC
ÆµÄèo·ïÐªoÄé©àµêÈ¢»¤Å·B

NTP EFuTCgÉÍ DSP vO (¨æÑ»êððàµ½ PDF t@C)
ª èÜ· http://www.eecis.udel.edu/~mills/resource.htmB±êÍZg
WIÆ TAPR/AMSAT DSP-93 Æ¢¤ (»ÝÅÍÌµÄ¢È¢) DSP Lbgðg
ÁÄ WWV ñðfR[h·éàÌÅ·B±ÌLbgÍ Texas Instruments Ì
TMS320C25 DSP `bvðx[XÉµ½àÌÅ·BTAPR ÌEFuTCg http://
www.tapr.org ÉÍ©ÐJÌ DSP vOÉÖ·éîñªLxÉ èÜ·
B

ntpd pbP[WÉÍ IRIG-B Æ IRIG-E ^CR[hÌhCo (type 6) à
ÜÜêÄ¢Ü·B±êÍ Sun SPARCstation Ì /dev/audio ðp·éàÌÅ
·ªA»êÈOÌVXeÉàÚAªÂ\¾»¤Å·B WWV ÅÍ IRIG-H ^C
R[hªgíêÄ¢Ü·B

WWV Í NIST Éæè^c³êÄ¨èAEFuTCgÍ http://
www.boulder.nist.gov/timefreq/index.html Å·B±ÌTCgÉÍ "Special
Publication 432" Æ¢¤¶ª èA±êÉÍÔÆügÉÂ¢ÄÌLqª
 èÜ·B http://www.boulder.nist.gov/timefreq/pubs/sp432/sp432.htm.
WWV Í 2.5, 5, 10, 15, 20 MHz ÅúµÄ¢Ü·B

ªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªª

4.3. GPS ÆuTotally Accurate Clockv

GPS MÉÍ³mÈÔàÜÜêÄ¢ÄAGPS V[oÌÈ©ÉÍVA|
[gðõ¦½àÌª èÜ·Bntpd ÉÍeí GPS V[opÌhCoª¯
«³êÄ¢Ü·B1PPS @\ ("One Pulse Per Second", ±êÍ©Èè¸xð
v·éêÉgíêéàÌÅ·) ÍAÊíÁÊÈC^[tFCXðgÁÄR
s[^Éq®Kvª èÜ·B

TAPR (Tuscon Amateur Packet Radio) ÉÍ TAC-2 ("Totally Accurate Clock"
Ìª) Æ¢¤C^[tFCXpÌLbgª èÜ·B±êÍVA|[g
É·µñÅ GPS V[oÆq®½ßÌC^[tFCXÅ èA1PPS Ìo
ÍðàÂ GPS V[oÈçÇñÈàÌÅàg¦Ü·BÜ½±êÉÍñHîÕÉ
¼ÚÚ¹é±ÆªÅ«éxA{[hf (bare board model) à èÜ·B
ÚµÍ http://www.tapr.org/ ÌEFuTCgð²¾³¢B(1999N6
_ÅÌ) liÍAGPS V[o²«Å 140 hOãÅ·B±ÌLbgÉÍâ
ÌâñHîÕæèt¯pÌiÍÜÜêÄ¢Ü¹ñB

(ÊÌÍÅq×½) CHU uGadget Boxvà 1PPS MÌC^[tFCXÆµÄ
g¤±ÆªÅ«Ü·BNTP EFuTCgÉÍ±êÉÖ·éà¾ªLÚ³êÄ¢
Ü· http://www.eecis.udel.edu/~ntp/ntp_spool/html/pps.htmB

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4.4. ·g^CVOiF DCF77, MSF(Rugby), WWVB

·gúÇÅÍALAÌIEItØèÖ¦ÉæÁÄ^CVOiðú
µÄ¢Ü·BúÇ²ÆÉÆ©ÌR[hû®ðgÁÄ¨èA»ÌTvÍ NTP
EFuTCgÉfÚ³êÄ¢Ü·Bhttp://www.eecis.udel.edu/~mills/ntp/
index.htm (±Ìy[WÌÅãÌÙ¤Å·)BhCcÌ DCF77 ÅÍ 77.5kHzAC
MXÌ MSF (±±ÍÝnÉ¿ÈñÅ "Rugby" ÆàÄÎêÄ¢Ü·) ÆR
hÌ WWVB ÍÇ¿çà 60 kHz Åú³êÄ¢Ü·B

WWVB ÌóM´xÍêèµÄ¢Ü¹ñªAúoÍðiKIÉã°æ¤Æ¢¤v
æª èÜ·B»Ìi»óµÉÂ¢ÄÍ NIST ÌEFuTCgð²¾³¢ 
http://www.boulder.nist.gov/timefreq/wwvstatus.html B

VA|[gÉÚ±Å«éÀ¿ÈV[oª[bpÅüèÂ\¾»¤Å
·B ntpd ÉÍ¢Â©Ì MSF V[opÌhCoªÜÜêÄ¢Ü·B

OÌ½ÌïÐª WWVB V[oðgÝñ¾ärIÀ¿ÈvðÌµ
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ÌméÀèARs[^ÉÚ±Å«éÌÍ 2 @íµ© èÜ¹ñB

Ultralink Model 320 Æ¢¤vÍ (1999N6_Å) 120 höxÅ·ªA
±êÍVAC^[tFCXÆ ASCII ¶ÉæéR}hZbgªg¦é
æ¤ÉÈÁÄ¢Ü·B»êä¦AvOðìéÌÍ»êÙÇïµÈ¢Í
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s[^©ç 100 tB[gÜÅ£·±ÆªÅ«AVOiª¾çêÈ¢êÉ
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Ultralink ÅÍxA{[Åà 80 höxÅÌµÄ¢Ü·B±êÍ "BASIC
Stamp" V[YÌ}CNRg[Å®æ¤ÉÝv³êÄ¢Ü·BÚµ
ÍÌEFuy[Wð²¾³¢B http://www.ulio.com/timepr.html.

Arcron Technology ÍAVA|[gðIvVõµ½ìãvðñ 80
hÅÌµÄ¢Ü·B±êÉÍ Windows pÌ\tgEFAàÜÜêÄ¢Ü·
BÚµÍÌEFuy[Wð²¾³¢B http://www.arctime.com.

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5. ú{êóÉÂ¢Ä

ëóEëEEÉÂ¢ÄÍA<JF@linux.or.jp> ÜÅ¨è¢µÜ·B

|                                (1997
ó gìëp                       /01) 
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X                                (2001
V çUTi                       /10/ 
F                                06)  
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³ é³½                            
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Notes

[1] óFRs[^ÌNbNªÇÌöx³m©ð³¦ÄêéAÊMî 
    ñ¤Ìy[W http://www2.crl.go.jp/pub/jst/index-J.htmlª èÜ
    ·B