FastVision FASTCAMERA Series, Руководство пользователя, Страница: 19 / 32

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8.6 Internal Camera Memory
The camera contains at least 128 MB of internal memory which can be expanded to 1000
MB, which can be used to FIFO the input images, to allow burst exposure, and slow
readout operation. Only the image data in the selected ROI is stored. A serial command
or the positive edge of CC3 can be used to clear FIFO memory. In addition, the Camera
contains LUTs for conversion from 10 to 10 bit, or 8 bit data which can be uploaded via
the serial port.
8.6.1 Serial Commands
The following text will discuss the command and control commands to and from
the FastCamera40 via the Serial Interface. For those commands that have
multiple bytes of data associated with them the protocol would be:
<Command><len[23:16]><len[15:8]><len[7:0]><data1>…..<dataN>
In this example the command was 0x01 for configure DAC’s the 3 bytes of length
are necessary to accommodate being able to program the DATA FPGA via the
Serial Interface. In this instance the length would total 32 bytes. 32 bytes of data
would follow. The receiving machine will not go back to its idle state until 32
bytes of data are transferred across the serial interface. The following table lists
the commands and their encoding:
8.6.2 0x00 Serial Command
Use this to reset the serial interface. If you send zero over and over until the
camera sends a ‘?’ (0x3f) you will be back in sync without effecting the camera
state.
8.6.3 0x01 ADC settings Serial Command
If you need to adjust the control voltages of the sensor, then use this command.
Note: FastVision does NOT support using this command, if you change these
values from the factory values, the sensor will not work right and your image
quality will be poor. So if you don’t know what your doing don’t mess with this. If
you mess with this, just power off the camera and power it on again, and you will
be out of trouble.
8.6.4 0x02 and 0x03 ROI Serial Commands
These commands set the start and end line (0x02) and the starting and ending
column 0x03) of the sensor, read out and defines the size of the image. If you
want the highest possible frame rate, keep the last column in your ROI less than
2048 (40). This is not an issue on the FastCamera13.
8.6.5 0x04 Line Length Serial Command
This sets the number of pixel clocks per line. If you are using the full sensor on
the FastCamera40 this must be greater than or equal to 153, or 132 on the
FastCamera13. Set this to larger values to slow the data rate from the camera or
to get finer control of the exposure.
8.6.6 0x05 Exposure Time Serial Command
This is the exposure time in pixel clocks. For the standard camera this is 1/66.66
MHz steps or 15 ns steps. (Sorry it’s too hard to divide in the camera.) This must
be greater than the line time (that is the content of register 0x04). Default value is
1,066,666 (16 msec).