Meinberg IMS-FDM, Руководство по установке

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4 FDM - Frequency Deviation Monitoring
4.1.4.5 TPC FDM String
The TPC string is a sequence of 29 ASCII characters containing the REF time (with day-of-the-year), the time
deviation TD and the frequency deviation FD. The string starts with the SOH character (start-of-header, ASCII
code 01h) on time with the beginning of every new REF time second and ends with the characters Carriage-
Return (ASCII code 0Dh) and Line-Feed (ASCII code 0Ah). The letters displayed in italics are replaced by the
calculated values whereas the other characters are part of the string:
<SOH>288:10:11:29 -00.03F+50.01<CR><LF>
The meaning of the several values is described below:
288:10:11:29 the reference time from the upstream radio clock,
(day of year:hours:minutes:seconds)
" " or "?" if reference time is synchron then " " otherwise "?"
-00.03 the mains frequency deviation from the setpoint, resolution 1 mHz
F+50.01 The power line frequency, 10 mHz resolution
4.1.4.6 Computime Extended FDM String
The extended Computime string is a sequence of 42 ASCII characters containing the REF time (with date and
day-of-the-week), the time deviation TD and the frequency F. The string is send out at the beginning of every
new REF time second and ends with the characters Carriage-Return (Hex code 0Dh) and Line-Feed (Hex code
0Ah). The letters displayed in italics are replaced by the calculated values whereas the other characters are
part of the string:
T: 10:03:09:02:15:03:30 D: +000.378F:49.984 <CR><LF>
The meaning of the several values is described below:
T: 10:03:09:02 The date of the reference time from the preconnected clock,
(year:month:day:day-of-the-week / Monday = 01, Sunday = 07)
15:03:30 The reference time from the preconnected clock,
(hours:minutes:seconds)
D: +000.378 The time deviation between REF time and PL time,
with sign character (+/-), resolution: 1ms,
maximum: +-99.999s (the first digit is always 0!)
F: 49.984 The measured power line frequency with a resolution of 1 mHz
IMS-FDM Setup Guide Date: March 15, 2022 19