24
PRELIMINARY
1M28, 1M75, and 1M150 User’s Manual
03-32-00525-04
DALSA
jump distance via the 8-bit parameter Line jump (register 33, see sensor module register
description), whose value can be in the range 1 to 255. This mode is activated by bit 4 register 12.
Line hopping can also be used in a pre-defined ROI.
Line hopping also functions in MROI mode when flag EN_LINE_HOPPING register 0CH bit 4 is
set. The value for the line jump is in register 21H. The camera’s factory setting pre-defines 17
ROIs.
1.11 Flip Image Mode
In Flip Image mode, the readout direction of the sensor is inverted so that the image appears upside
down. This mode is activated by bit 2 register 12. See chapter 3 for details on working with the
camera registers.
1.12 Calculating Frame Rate
To determine the frame rate, it is easiest to calculate the frame time first. The frame rate is the
inverse of frame time.
The frame time depends on the parameters exposure time, ROI, and line pause.
For the frame time:
Frame time
> exposure time + read out time
> exposure time + t
U
([No. of lines]*([No. of Line pause)+ Line pause + CPRE)
> exposure time + t
U
((ROI_Y1-ROI_Y0)*((ROI_X1-Line pause) + Line pause +
CPRE)
with the boundary conditions :
t
U
= Time unit in ns (35ns for 1M28, 12.5ns for 1M75, and 6.25ns for 1M150)
CPRE = Clocks after exposure of the sensor, CPRE=42
Line pause = 5 … 255
ROI_Y1-ROI_Y0 = max. 1024 lines
ROI_X1-ROI_X0 = max. 1024 pixels
Notes:
•
If you are using multiple regions of interest, the number of pixels per active window must be
added to obtain
No. of lines
. If the line jump function is active, the number of lines read out
from the sensor will be reduced corresponding to the value of the line jump.
•
Frame rate is the reciprocal of frame time.
•
With an external MCLK, the time unit t
u
must match the frequency used.
•
More information on calculating frame rates is available at
http://vfm.dalsa.com/support/faqs/faqs.asp
.
