Command Setting And Operation Timing - Sony DFW-SX900 Technical Manual

DFW-SX900
DFW-X700

COMMAND SETTING AND OPERATION TIMING

The DFW-SX900/X700 operates synchronously with internal pulses called VD. VDs are reference signals inside the camera and
cannot be observed from outside the camera.
Even if commands are set to the CSR of the camera, it does not mean that they become effective the instant they have been
written. They become effective after the VD period set to the CSR has been completed and the next VD pulse is generated as
shown in the following figure. The command settings are set for video signals by the Isochronous output after that. (The timing at
which the command settings become effective may delay according to the internal state of the camera.)
When operating at a low frame rate even if the transmission time of one frame exceeds one VD, and the CSR settings are changed
during transmission, the command settings will not be set to the video signals until the frame currently being output is complete.
Set command to CSR in this period
VD
Isochronous
Isochronous
Isochronous Transmission Start/Stop command and actual operation timing
As shown in the following figure, it takes at least about 1 V for the actual isochronous transmission of image data to start or
stop after the Isochronous Start/Stop command (CSR F0F00614h: ISO_EN) has been set to the CSR of the camera. (VDs are
the reference signals inside the camera and cannot be observed from outside the camera.)
Isochronous transmission start/stop is executed in units of frames. Isochronous transmission will not start/stop before one
image output ends. This means that if a low frame rate at which the transmission of one image takes a long time is selected, the
time taken for executing Isochronous Stop will be long.
Set Iso ON/OFF in this period
VD
Isochronous
Isochronous
If Shutter (CSR F0F0081Ch) is set to the extended exposing mode, command execution may delay for the exposure time at
maximum in addition to the previous delay for both Isochronous Start/Stop.
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Setting becomes effective in
next VD period (or the next)
1 V
1 V = Approx. 133 ms (DFW-SX900)
Approx. 67 ms (DFW-X700)
1 V
Command settings are set to isochronous
output after setting becomes effective
When low frame rate is selected, command
settings are set to isochronous output after
completion of isochronous output before setting
Approx. 8.0 ms (DFW-SX900)
Approx. 2.4 ms (DFW-X700)
ON ON/OFF is executed with an
interval of 1 V from V period set
OFF
Low Frame Rate
7.5 Frame/s (DFW-SX900)
15 Frame/s (DFW-X700)
OFF