Specifications

Comedi

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Return value

The new buffer size in bytes is returned on success. On error, -1 is returned.

5.4.2.16 comedi_set_max_buffer_size

comedi_set_max_buffer_size — streaming maximum buffer size of subdevice

Synopsis

#include <comedilib.h>

int comedi_set_max_buffer_size(comedi_t * device, unsigned int subdevice, unsigned int max_size);

Description

The function comedi_set_max_buffer_size() changes the maximum allowable size (in bytes) of the streaming buffer

for the subdevice speciﬁed by device and subdevice. Changing the maximum buffer size requires the user to have appropriate

privileges.

Return value

The new maximum buffer size is returned on success. On error, -1 is returned.

5.4.3 Calibration

5.4.3.1 comedi_apply_calibration

comedi_apply_calibration — set hardware calibration from ﬁle

Synopsis

#include <comedilib.h>

int comedi_apply_calibration(comedi_t * device, unsigned int subdevice, unsigned int channel, unsigned int range, unsigned

int aref, const char * ﬁle_path);

Status

alpha

Description

The function comedi_apply_calibration() sets the hardware calibration for the subdevice speciﬁed by device and s-

ubdevice so that it is in proper calibration when using the channel speciﬁed by channel, range index speciﬁed by range

and analog reference speciﬁed by aref. It does so by performing writes to the appropriate channels of the board’s calibration

subdevice(s). Depending on the hardware, the calibration settings used may or may not depend on the channel, range, or analog

reference. Furthermore, the calibrations appropriate for different channel, range, and analog reference parameters may not be able

to be applied simultaneously. For example, some boards cannot have their analog inputs calibrated for more than one input range

simultaneously. Applying a calibration for range 1 may blow away a previously applied calibration for range 0. Or, applying

a calibration for analog input channel 0 may cause the same calibration to be applied to all the other analog input channels as

well. Your only guarantee is that calls to comedi_apply_calibration() on different subdevices will not interfere with

each other.