1 Radio Timecode Formats (README.timecodes)
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.
11 C on-time character (start bit)
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)
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.
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 ^.
33 Spectracom 8170 and Netclock/2 WWV Synchonized Clock (format 0)
35 "<CR><LF>i ddd hh:mm:ss TZ=zz<CR><LF>"
38 poll: ?; offsets: Y = none, D = 3, T = 7, A = 0, Q = none
39 i = synchronization flag (<SP> = in synch, ? = out synch)
41 hh:mm:ss = hours, minutes, seconds
42 zz = timezone offset (hours from UTC)
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
48 example: " 216 15:36:43 TZ=0"
51 Netclock/2 WWV Synchonized Clock (format 2)
53 "<CR><LF>iqyy ddd hh:mm:ss.fff ld"
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
60 yy = year (as broadcast)
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)
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.
72 example: " 92 216 15:36:43.640 D"
75 TrueTime 468-DC Satellite Synchronized Clock (and other TrueTime
78 "<CR><LF><^A>ddd:hh:mm:ssq<CR>"
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)
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>
90 example: "216:15:36:43 "
93 Heath GC-1000 Most Accurate Clock (WWV/H)
95 "<CR>hh:mm:ss.f dd/mm/yy<CR>"
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)
102 yy = year of century (from DIPswitches)
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
108 example: "15:36:43.6 04/08/91"
111 PST/Traconex 1020 Time Source (WWV/H) (firmware revision V4.01)
113 "frdzycchhSSFTttttuuxx<CR>" "ahh:mm:ss.fffs<CR>" "yy/dd/mm/ddd<CR>"
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)
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)
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)
135 yy = year of century (from DIPswitches)
136 dd/mm/ddd = day of month, month of year, day of year
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.
143 example: "O3@055281824C00000394 91/08/04/216 15:36:43.640"
147 University of Delaware