evertz 8083XDS-AD Instruction Manual page 127

•
Once the clock has been initially set, it only updates from the XDS packets once per hour at the
beginning of the minute except between 11:00 p.m. and 2:00 a.m. To force the clock to update at
other times, you have to turn off the AUTO CLOCK mode then turn it back on, and then power down
the VCR. The clock will then update at the beginning of the next minute if there are valid Time of
Day and Time Zone packets present.
A.6.4. Notes about Sony VCRs
•
When they are in the AUTO CLOCK mode, they search for incoming signals with XDS time of day
and time zone packets when they are first plugged in. They only update from the XDS packets at
the beginning of the minute. The VCR can also lock onto the time by simply powering the unit on
and then off. When this happens, the time will only get updated at the beginning of a minute.
•
The Time Zone packets MUST be present for the AUTO CLOCK feature in these VCRs to work. In
areas that do not encode Time Zone packets, in accordance with EIA-608-B rules, the AUTO
CLOCK function in these VCRs will not work.
•
If the VCR is receiving Time of Day and Time Zone packets, its clock will be updated depending on
its timezone and DST settings. If the timezone is set manually in the VCR, the clock will be updated
with the VCR timezone setting rather than pulling it off the 8084 packets.
•
VCR does not look for the DSO flag in the Time Zone packet. The VCR can be set for DST
On/Off/Auto. When it is set to Auto the VCR follows the DST flag bit in the Time of Day packet as
long as both packets are present. In regions that do not observe DST the VCR must be set to DST
Off.
•
VCR will not automatically do rollovers for Daylight Saving Time if Time of Day and Time Zone
packets are not present. The VCR needs to be turned off and then on to adjust to the correct time
again.
A.6.5. Time Zones East of Greenwich
EIA-608B specifies that time zones are always interpreted as a negative whole hour offset from UTC.
This means that time zones east of Greenwich and west of the International Date Line will be encoded
as –23 to –13 hour offsets. Some VCRs may not realize that these time zones are on the opposite side
of the International Date line and hence may decode the date incorrectly. If this happens, the Time
Zone packets should not be encoded. (See note in section 3)
A.6.6. Miscellaneous Issues
•
Some VCRs will only update their clocks once per hour
•
Some VCRs will only update their clocks accurate to the minute
•
Some VCRs only update their clocks one time after power up.
APPLICATION NOTES
8083XDS-AD Analog and SD-SDI XDS Encoder
Revision 1.0.2
AN-13