T-VIPS CP560, User Manual

Page: 125 / 200

WEB Interface 125
ID: um_t2gateway CP560 DVB-T2 Gateway User’s Manual Rev. 2.2 (3686)
Transport Stream (input). This feature is usefull when performing “over-air” synchroniza-
tion using re-transmitters. The PID for the MIP packets is 21 (hex 15).
Note: This functionality is only active when SFN (Time Stamp Frame) is
active.
Timestamp type
This field indicates the type of the time stamp to be sent to the modulator. Possible values
are:
• Null: Seconds and subsecond field set to 1’s. For MFN networks.
• Relative: Seconds field set to 0’s, while subsecond field locked to 1PPS.
•
Absolute: Seconds field locked to SNTP, subsecond field locked to 1PPS.
Estimated transmission time
This field indicates the time (in ms) the DVB-T2 frames are sent ahead of the transmission
time. Relevant for Relative and Absolute Timestamps. This value should take into account
all delays (buffers) from the CP560 to the transmission time in the modulator.
If using Absolute timestamp or using the CP560 in a Seamless SFN system leap seconds must
be handled. If not, leap seconds may be ignored.
Leap seconds since 2000
This is the current amount of leap seconds accounted for since 2000. This value will be
updated when a new leap second is added. The number of leap seconds is persistent, such
that if the units reboots after a leap second have been added, it will boot with the new
amount of leap seconds. Press
Refresh to update the current number of leap seconds. Per
August 2012 the current number of leap seconds is 3. Leap seconds increased from 2 to 3
on June 30, 2012 at 23:59:60 UTC.
Warning: Manually changing the amount of leap seconds runtime will
affect the internal packet scheduling and may cause glitches in the outgoing
stream.
Leap second transition
The amount of leap seconds to adjust with when the Transition Date expires. Allowed
values are +1 and -1. If set to none, leap second handling is effectively disabled.
Transition Date [UTC]
Set the date for when to add the next leap second. Transition time and increment is
determined and announced by the International Earth Rotation and Reference Systems
Service (IERS)
1
.
http://www.iers.org
1