Basler Vision Technologies Sprint Series, Руководство пользователя

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Configuring the Camera
164 Basler sprint Mono Cameras
7.2.2 Feature Control and Status Registers
The feature control and status registers (CSRs) let you set the parameters for camera features such
as exposure mode, gain, offset, and the AOI. These registers also let you check the current
parameter settings and the status for each feature.
Each feature has one or more CSRs associated with it. The fields within a feature’s CSR(s) are
used to control how the feature operates. By using binary write commands to write to fields within
a feature’s CSR(s), you can change the parameter settings for the feature. By using binary read
commands, you can determine the current setting for the parameters and get information about the
feature’s status.
The address for any field within a register is equal to the register base address plus the offset for
the field. Look at the Video Data Output Mode CSR on
page 173 as an example. The Mode field of
this register has an address of 0x1701 (the base address of 0x1700 plus the offset of 0x0001). By
writing a value to this address, you can set the video data output mode. By reading the value at this
address, you can determine the current output mode setting.
The Video Data Output Mode CSR is a simple CSR with only two fields. Most of the other feature
CSRs have several read/write fields that let you set the parameters associated with the feature.
They may also have read only fields that contain information about the minimum and maximum
allowed setting for each parameter. Section 7.2.2.2 on
page 166 lists the feature CSRs in the
camera and shows detailed information about the use of each field within the register.
7.2.2.1 “Raw” Value Fields vs. “Absolute” Value Fields
As you look through the descriptions of the feature CSRs, you will notice that some CSRs have a
parameter that can be set by writing a value to a “raw” field or by writing a value to an “absolute”
field. You will find this to be true for the Exposure Time, Line Period, Gain, and Offset parameters.
The common characteristic among these parameters is that they are “scalar”, i.e., they can be set
to a value within a continuous scale rather than just a small set of individually defined values. Any
one of these scalar parameters can be set on a “raw” scale or on an “absolute” scale. A raw scale
is simply a range of integer values that has no defined units. An absolute scale is a range of floating
point values that has defined units.
Consider the Gain parameter as an example:
Setting the Raw Gain
If you set the gain by writing a value to the Raw Gain field of the Gain CSR, you can write any integer
value from 1024 to 16383 (decimal). Writing an integer value to the raw register sets the gain, but
it doesn’t directly tell you how many dB of gain you will be getting from the camera at that setting.
To determine the dB of gain you are getting at a particular raw gain setting, you must use the
formula:
Gain in dB 20 log
10
setting
4096
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