Huahuan Electronics HX.PTP-GM02, User Manual

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Beijing Huahuan Electronics Co., Ltd
Figure 6-8 1PPS+ToD settings
1PPS cable delay compensation in nanosecond is used to enter the amount of
delay due to the limited transmission speed of the signal in the twisted pair cable.
The estimated delay for CAT5 cable is 5.02ns/s. When the cable length is 500
meters for example, it will introduce 2150ns, or 2.15
µ
s delay. This delay is still
very small for many applications, and compensation may not be necessary. But
for some applications, for example 4G/5G mobile communication systems, this
delay may not be tolerable and must be compensated for. Measure or estimate the
cable delay, enter the number in the box to make the signal pulse edge come out
of the port earlier by the specified amount. Note that the compensation is made in
5ns steps, the entered number will be automatically rounded accordingly.
ToD messages specify the exact time instant of each rising edge of the 1PPS
pulse, as well as a number of other information useful for the client. This message
is not sensitive to delays of millisecond range, so delay compensation does not
affect ToD. But there are different flavors of ToD message format. The
GeckoSynco has two built-in formats to choose from, namely the CMCC standard
by China Mobile Communications Corporation, and G.8271 recommended by
ITU-T.
Do not forget to click the Apply button for new settings to take effect.
30 HX.PTP-GM02 IEEE-1588 Grandmaster Clock V1.0