78
Zektor Switch Serial Protocol, Version 0.16, 5/13/16
Audio Control
per second. To calculate the value needed to delay a set number of frame, divide the frames per second
into 48000, and multiply by the number of frames to delay. For instance if your video signal is 60
frames per second, and you want to delay zone 3 by 2 frames: (48000 / 60fps) * 2 = 1600
^LSZ @3,1600
->
Delay zone 3 by 1600 samples (two 60fps frames)
^LSZ @2,+800
->
Add one 60fps frame of delay to zone 2
‘LSI’ Set Lip Sync delay for an Input
Each source is capable of delaying audio for up to 170.65mS. The delay resolution is 1/48000 of a sec-
ond, or 48 counts per millisecond.
Command format:
^LSI @
in
,@
in
,
delay
Set the lip sync delay an source or sources.
^LSI @
in
,+
step
$
Add ‘step’ to source’s delay.
^LSI @
in
,-
step
$
Subtract ‘step’ from source’s delay.
Response Strings:
^=LSI @
in
,
delay
$
Where:
@
in
= One (or more) sources to be affected.
delay
= Lip sync delay in 48KHz samples, each count delays audio by 1/48000 of a second.
A value of 0 indicates no delay.
There are two forms of the lip sync delay commands, the ‘LSZ’ command which sets lip sync delay on
a zone by zone basis, and the ‘LSI’ command which sets delays on a source by source basis. Which
one to use depends on what is causing the video delay, and where it’s connected in the video path.
If the source of a video processor (or monitor) that adds a video delay is connected to a zone, then the
‘LSZ’ command should be used to delay the audio by the same amount of time the video is being
delayed. Only audio that is being sent to the video processor, attached to the zone, will be delayed.
If on the other hand, if the output of a video processor that adds a video delay, is connected to an
source, then the ‘LSI’ command should be used. This allows all zones that connect to the video proces-
sor, to have their delays automatically adjusted to compensate for the processor’s video delays.
Both sources and zones can have delays set, however the overall delay cannot exceed 8191 counts (or
170.65mS). If an source and zone combination exceeds 8191 counts, no error will be generated and the
delay will be set to 8191.
For examples, see the examples of the ‘LSZ’ command on page 77.