Teledyne Princeton Instruments PICam 5.x, Programmer'S Manual

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Chapter 6: Data Acquisition APIs
Once system hardware has been configured and the parameters are committed, the
system is ready to acquire data. Data can be acquired either synchronously or
asynchronously.
By default, memory is allocated automatically to accommodate the data. This
automatic memory is valid until the next acquisition or until the hardware is closed.
Alternatively, the automatic memory management can be replaced with a user-
allocated buffer by calling
PicamAdvanced_SetAcquisitionBuffer()
. The buffer
can be any size as long as it can contain at least one readout. Typically, using a user-
allocated buffer is optional. However, configuring the hardware such that the total
number of readouts is indeterminate will disable automatic memory management and
require a user-allocated buffer. This will occur if one:
• Instructs the hardware to acquire more data than it can exactly acquire;
This is achieved by setting
PicamParameter_ReadoutCount
to a value
greater than the value of
PicamParameter_ExactReadoutCount
Maximum
.
• Instructs the hardware to readout data non-destructively (for hardware that
supports this feature).
• Instructs the hardware to acquire data indefinitely
This is achieved by setting
PicamParameter_ReadoutCount
to 0.