Sony XCD-V60 - Manual (Page 13)

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Memory Shot
The camera is equipped with Memory Shot that
temporarily stores an image in the frame memory inside
the camera and transfers it later.
When multiple cameras are connected in the same bus,
all the cameras may not output images at the same time
due to the restriction of 800 Mbps band. Memory Shot
may resolve this inconvenience.
When exposure starts, each camera stores an image in
the frame memory without allocating the isochronous
resource.
When outputting, each PC outputs the image from the
camera allocating the isochronous resource.
The number of images to be stored depends on the video
mode.
Broadcast Command
The normal1394 communication method specifies the
node number at the host side so that only a specified
camera responds to the command.
If the node number is set to 63, all the cameras
connected to the same bus can receive the command
simultaneously, i.e., only one command issued from the
host can control multiple cameras at the same time.
Example: To broadcast a software trigger
1. Connect multiple cameras to the same bus.
2. Set the video mode and frame rate appropriately on
each camera and prepare the cameras for sending
images at the same time.
3. Set each camera to the software trigger mode.
4. Issue a software command for node number 63.
Now all the cameras start exposure and output images
simultaneously.
All the commands including the video mode setting and
the feature control are capable of broadcasting except
the block writing command.
When setting different types of cameras using a
broadcast command, be careful not to issue a command
that the cameras do not support.
1394 Bus
Synchronization
Timing used to start exposure is synchronized with the
1394 bus time cycle register.
If cameras are connected to the same bus, they are
automatically synchronized in a 1394 bus operation. As
800 Mbps band restriction can affect the
synchronization, you must set the video mode in which
the cameras can transmit a video signal at the same time.
1394 synchronization does not work in long exposure
mode and Partial scan mode. In a long exposure, the
exposure time is set longer than the image transmission
cycle.
1394 bus synchronization includes up to 1H cycle jitter.
Hardware external synchronization will ensure greater
accuracy.