Silicon Imaging SI-3300 MegaCamera, Инструкция по эксплуатации

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Silicon Imaging , Inc. 2004 Page 14 of 39 Company Confidential
Digital Clock Synthesizer Programming
The SI-3300 has a Digital Clock Synthesizer capable of generating a range of frequencies from 20MHz to 40 or up
80Mhz with –H version. The pixel data output rate is the same as the sampling clock rate. The clock frequency is set
by the “lc” Register String command. A range of sample frequencies are listed below:
Command
Clock Rate
MHz
SI-3300 Frame Rate
MHz 2048 x 1536 1600 x1200 1920x1080 1280x720 640 x480 320 x240 128 x128
lc306886 20 5 8 8 17 40 122 148
lc30b689 25 7 10 10 21 50 152 185
lc37cb8f 30 8 13 12 25 60 182 222
lc35d40b 35 9 15 14 29 70 213 259
lc306882 40 11 17 16 33 80 243 296
lc35e709 45 12 19 18 37 90 274 333
lc36a20f 48 13 20 19 40 96 292 355
lc34b689 50 13 21 20 41 100 304 370
lc34b688 55 15 23 22 45 110 334 407
lc36cb8f 60 16 25 24 50 120 365 444
lc367307 65 17 27 26 54 130 395 481
lc36ee0f 70 19 29 28 58 140 426 518
lc36f88f 73 19 30 29 60 147 446 542
lc34ae05 75 20 31 30 44 75 20 31 30 62 150 456 555
Note: The factory can generate the command to achieve a targeted clock rate.
Sample Command:
The clock frequency is programmed by the “lc” command with by 6 HEX characters. An example is:
“ lc36cb8f <cr>” This will request a clock value of 60MHz.
The response to a command will be:
114: Clock updated
Frame Rate Calculation
There is a minimum of 390 clocks of Horizontal Blanking (Reg x05 = 21) and of 4 rows of Vertical Blanking (Reg x06
= 3). To calculate the frame rate for any clock rate the equation is estimated by:
( clock rate(Hz) ) = #
Frames Per Second (fps)
( # of c 390) * ( # of rows +4)
Example:
What is the frame rate, at 45MHz clock rate for an image size of 2048 x 1536?
40 x 10
6
= 11
Frames Per Second (fps)
( 2048 + 390) * (1536 +4)
** Subsampling frame rates are based on the resulting size of the sub-sampled image or window.
*** Minimum # of columns that are internally clocked is 257, even if the image window is smaller. Therefore the
minimum row time = 257 + 390 blanking = 647 clocks.