1: Radio Timecode Formats (README.timecodes)
2:
3: Following are examples of the serial timecode formats used by various
4: timecode receivers as given in the instruction manuals. These examples
5: are intended only for illustration and not as the basis of system
6: design. The following symbols are used to identify the timecode
7: character that begins a subfield. The values given after this symbol
8: represent the character offset from the beginning of the timecode string
9: as edited to remove control characters.
10:
11: C on-time character (start bit)
12: Y year of century
13: T time of day
14: D day of year or month/day
15: A alarm indicator (format specific)
16: Q quality indicator (format specific)
17: <LF> ASCII line feed (hex 0a)
18: <CR> ASCII carriage return (hex 0d)
19: <SP> ASCII space (hex 20)
20:
21: In order to promote uniform behavior in the various implementations, it
22: is useful to have a common interpretation of alarm conditions and signal
23: quality. When the alarm indicator it on, the receiver is not operating
24: correctly or has never synchronized to the broadcast signal. When the
25: alarm indicator is off and the quality indicator is on, the receiver has
26: synchronized to the broadcast signal, then lost the signal and is
27: coasting on its internal oscillator.
28:
29: In the following uppercase letters, punctuation marks and spaces <SP>
30: stand for themselves; lowercase letters stand for fields as described.
31: Special characters other than <LF>, <CR> and <SP> are preceded by ^.
32:
33: Spectracom 8170 and Netclock/2 WWV Synchonized Clock (format 0)
34:
35: "<CR><LF>i ddd hh:mm:ss TZ=zz<CR><LF>"
36: C A D T
37:
38: poll: ?; offsets: Y = none, D = 3, T = 7, A = 0, Q = none
39: i = synchronization flag (<SP> = in synch, ? = out synch)
40: ddd = day of year
41: hh:mm:ss = hours, minutes, seconds
42: zz = timezone offset (hours from UTC)
43:
44: Note: alarm condition is indicated by other than <SP> at A, which
45: occurs during initial synchronization and when received signal has
46: been lost for about ten hours
47:
48: example: " 216 15:36:43 TZ=0"
49: A D T
50:
51: Netclock/2 WWV Synchonized Clock (format 2)
52:
53: "<CR><LF>iqyy ddd hh:mm:ss.fff ld"
54: C AQY D T
55:
56: poll: ?; offsets: Y = 2, D = 5, T = 9, A = 0, Q = 1
57: i = synchronization flag (<SP> = in synch, ? = out synch)
58: q = quality indicator (<SP> < 1ms, A < 10 ms, B < 100 ms, C < 500
59: ms, D > 500 ms)
60: yy = year (as broadcast)
61: ddd = day of year
62: hh:mm:ss.fff = hours, minutes, seconds, milliseconds of day
63: l = leap-second warning (L indicates leap at end of month)
64: d = standard/daylight time indicator (<SP> standard, D daylight)
65:
66: Note: alarm condition is indicated by other than <SP> at A, which
67: occurs during initial synchronization and when received signal has
68: been lost for about ten hours; unlock condition is indicated by
69: other than <SP> at Q, with time since last lock indicated by the
70: letter code A < 13 min, B < 1.5 hr, C < 7 hr, D > 7 hr.
71:
72: example: " 92 216 15:36:43.640 D"
73: AQ D T
74:
75: TrueTime 468-DC Satellite Synchronized Clock (and other TrueTime
76: receivers)
77:
78: "<CR><LF><^A>ddd:hh:mm:ssq<CR>"
79: D T QC
80:
81: poll: none; offsets: Y = none, D = 0, T = 4, A = 12, Q = 12
82: hh:mm:ss = hours, minutes, seconds
83: q = quality/alarm indicator (<SP> = locked, ? = alarm)
84:
85: Note: alarm condition is indicated by ? at A, which occurs during
86: initial synchronization and when received signal is lost for an
87: extended period; unlock condition is indicated by other than <SP>
88: at Q
89:
90: example: "216:15:36:43 "
91: D T Q
92:
93: Heath GC-1000 Most Accurate Clock (WWV/H)
94:
95: "<CR>hh:mm:ss.f dd/mm/yy<CR>"
96: C T A D
97:
98: poll: none; offsets: Y = none, D = 15, T = 0, A = 9, Q = none
99: hh:mm:ss = hours, minutes, seconds
100: f = deciseconds (? when out of spec)
101: dd/mm = day, month
102: yy = year of century (from DIPswitches)
103:
104: Note: 0?:??:??.? is displayed before synch is first established and
105: hh:mm:ss.? once synch is established and then lost again for about
106: a day.
107:
108: example: "15:36:43.6 04/08/91"
109: T A D Y
110:
111: PST/Traconex 1020 Time Source (WWV/H) (firmware revision V4.01)
112:
113: "frdzycchhSSFTttttuuxx<CR>" "ahh:mm:ss.fffs<CR>" "yy/dd/mm/ddd<CR>"
114: A Q T Y D
115:
116: poll: "QMQDQT"; offsets: Y = 0, D = 3 T = 1,, A = 11, Q = 13
117: f = frequency enable (O = all frequencies enabled)
118: r = baud rate (3 = 1200, 6 = 9600)
119: d = features indicator (@ = month/day display enabled)
120: z = time zone (0 = UTC)
121: y = year (5 = 1991)
122: cc = WWV propagation delay (52 = 22 ms)
123: hh = WWVH propagation delay (81 = 33 ms)
124: SS = status (80 or 82 = operating correctly)
125: F = current receive frequency (1-5 = 2.5, 5, 10, 15, 20 MHz)
126: T = transmitter (C = WWV, H = WWVH)
127: tttt = time since last update (minutes)
128: uu = flush character (03 = ^C)
129: xx = 94 (unknown) (firmware revision X4.01.999 only)
130:
131: a = AM/PM indicator (A = AM, P = PM, <SP> - 24-hour format)
132: hh:mm:ss.fff = hours, minutes, seconds, milliseconds of day
133: s = daylight-saving indicator (<SP> standard, D daylight)
134:
135: yy = year of century (from DIPswitches)
136: dd/mm/ddd = day of month, month of year, day of year
137:
138: Note: The alarm condition is indicated by other than ? at A, which
139: occurs during initial synchronization and when received signal is
140: lost for an extended period. A receiver unlock condition is
141: indicated by other than "0000" in the tttt subfield at Q.
142:
143: example: "O3@055281824C00000394 91/08/04/216 15:36:43.640"
144: T Y D T
145:
146: David L. Mills
147: University of Delaware
148: mills@udel.edu
149: 23 October 1993
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