MV-D752-28 User’s Manual
REV: 1.0
Page 16/61
5.3
Trigger mode with external edge triggered exposure control
In trigger mode with external edge triggered exposure control, sensor control is reset
with the rising edge of an external trigger pulse (POLARITY_SYNC_EXPOSURE = ‘1’) and
the exposure of the image begins. The integration ends with the rising edge of the
external signal EXPOSURE (POLARITY_SYNC_EXPOSURE = ‘1’). The signals EXSYNC and
EXPOSURE are clocked in the sensor control in such a way that the internal exposure
control becomes active one clock (35 ns in case of internal clock) later (see SHUTTER
signal). If necessary, the polarity of the EXSYNC signal can be matched to that of the
frame grabber by means of the flag POLARITY_SYNC_EXPOSURE bit 3 mode register 3.
The image is read out after the exposure time has elapsed. After readout, the sensor
returns to the reset state and the camera waits for a new trigger pulse.
The data are output on the rising edge of the pixel clock. The signals FRAME_VALID
(FVAL) and LINE_VALID (LVAL) mask valid image information. The signal SHUTTER
indicates the active integration phase of the sensor. The number of clock pulses after
exposure
CPRE
is defined by the calculation of the frame time (see 9).
Fig. 7: Timing Diagram Trigger Mode with external edge triggered exposure
control
EXPOSURE
EXSYNC is ignored in mode constant image data rate
PCLK
SHUTTER
FVAL
DATA
EXSYNC
LVAL
line pause
first line line pause last line
CPRE
Integration
line paus
e