760 lines
28 KiB
Text
760 lines
28 KiB
Text
Function: comedi_close -- close a Comedi device
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Retval: int
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Param: comedi * device
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Description:
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Close a device previously opened by comedi_open().
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Returns:
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If sucessful, comedi_close returns 0. On failure, -1 is returned.
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Function: comedi_open -- open a Comedi device
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Retval: comedi_t
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Param: const char * filename
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Description:
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Open a Comedi device specified by the file filename.
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Returns:
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If sucessful, comedi_open returns a pointer to a valid comedi_t
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structure. This structure is transparent; the pointer should not
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be dereferenced by the application. NULL is returned on failure.
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Function: comedi_loglevel -- change Comedilib logging properties
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Retval: int
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Param: int loglevel
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Description:
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This function affects the output of debugging and error messages
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from Comedilib. By increasing the loglevel, additional debugging
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information will be printed. Error and debugging messages are
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printed to the stream stderr.
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The default loglevel can be set by using the environment variable
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COMEDI_LOGLEVEL. The default loglevel is 1.
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In order to conserve resources, some debugging information is
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disabled by default when Comedilib is compiled.
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The meaning of the loglevels is as follows:
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COMEDI_LOGLEVEL=0 Comedilib prints nothing.
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COMEDI_LOGLEVEL=1 (default) Comedilib prints error messages when
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there is a self-consistency error (i.e., an internal bug.)
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COMEDI_LOGLEVEL=2 Comedilib prints an error message when an invalid
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parameter is passed.
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COMEDI_LOGLEVEL=3 Comedilib prints an error message whenever an
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error is generated in the Comedilib library or in the C library,
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when called by Comedilib.
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COMEDI_LOGLEVEL=4 Comedilib prints a lot of junk.
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Returns:
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This function returns the previous loglevel.
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Function: comedi_perror -- print a Comedilib error message
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Retval: void
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Param: const char * s
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Description:
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When a Comedilib function fails, it usually returns -1 or
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NULL, depending on the return type. An internal library
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variable stores an error number, which can be retrieved with
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comedi_errno(). This error number can be converted to a
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human-readable form by the functions comedi_perror()
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and comedi_strerror().
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These functions are intended to mimic the behavior of the
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standard C library functions perror(), strerror(), and errno.
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In particular, Comedilib functions sometimes return an error
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that is generated inside the C library; the comedi error
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message in this case is the same as the C library.
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The function comedi_perror() prints an error message to stderr.
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The error message consists of the argument string, a colon, a
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space, a description of the error condition, and a new line.
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Function: comedi_strerror -- return string describing Comedilib error code
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Retval: char *
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Param: int errnum
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Description:
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When a Comedilib function fails, it usually returns -1 or
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NULL, depending on the return type. An internal library
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variable stores an error number, which can be retrieved with
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comedi_errno(). This error number can be converted to a
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human-readable form by the functions comedi_perror()
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and comedi_strerror().
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These functions are intended to mimic the behavior of the
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standard C library functions perror(), strerror(), and errno.
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In particular, Comedilib functions sometimes return an error
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that is generated inside the C library; the comedi error
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message in this case is the same as the C library.
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The function comedi_strerror() returns a pointer to a
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character string
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describing the Comedilib error errnum. The persistence
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of the returned pointer is undefined, and should not be trusted
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after the next Comedilib call. An unrecognized error number will
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return a pointer to the string "undefined error", or similar.
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Function: comedi_errno -- number of last Comedilib error
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Retval: int
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Param: void
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Description:
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When a Comedilib function fails, it usually returns -1 or
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NULL, depending on the return type. An internal library
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variable stores an error number, which can be retrieved with
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comedi_errno(). This error number can be converted to a
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human-readable form by the functions comedi_perror()
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and comedi_strerror().
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These functions are intended to mimic the behavior of the
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standard C library functions perror(), strerror(), and errno.
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In particular, Comedilib functions sometimes return an error
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that is generated inside the C library; the comedi error
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message in this case is the same as the C library.
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The function comedi_errno() returns an integer describing
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the most recent comedilib error. This integer may be used
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as the errnum parameter for comedi_strerror().
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Note that comedi_errno() is deliberately different than the
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variable errno. This is to overcome difficulties in making
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errno thread-safe.
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Function: comedi_fileno -- integer descriptor of Comedilib device
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Retval: int
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Param: comedi_t * device
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Description:
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The function comedi_fileno returns the integer descriptor for
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the device dev. This descriptor can then be used as the
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file descriptor parameter of read(), write(), etc.
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This function is intended to mimic the standard C library
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function fileno(). If dev is an invalid comedi_t
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pointer, the function returns -1 and sets the appropriate
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Comedilib error value.
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Function: comedi_get_n_subdevices -- number of subdevices
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Retval: int
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Param: comedi_t * device
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Description:
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Returns the number of subdevices belonging to the Comedi
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device referenced by the parameter device.
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Function: comedi_get_version_code -- Comedi version code
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Retval: int
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Param: comedi_t * device
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Description:
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Returns the Comedi kernel module version code. A valid Comedi
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device referenced by the parameter device is necessary to
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communicate with the kernel module. On error, -1 is returned.
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The version code is encoded as a bitfield of three 8-bit
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numbers. For example, 0x00073d is the version code for
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version 0.7.61.
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This function is of limited usefulness. A typical
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mis-application of this function is to use it to determine
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if a certain feature is supported. If the application needs
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to know of the existence of a particular feature, an existence
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test function should be written and put in the Comedilib source.
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Function: comedi_get_driver_name -- Comedi driver name
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Retval: char *
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Param: comedi_t * device
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Description:
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The function comedi_get_driver_name returns a pointer
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to a string containing the name of the driver being used by comedi
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for the comedi device represented by device. This pointer is
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valid until the device is closed. This function returns NULL
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if there is an error.
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Function: comedi_get_board_name -- Comedi device name
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Retval: char *
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Param: comedi_t * device
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Description:
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The function comedi_get_board_name returns a pointer
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to a string containing the name of the device. This pointer is
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valid until the comedi descriptor it is closed. This
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function returns NULL if there is an error.
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Function: comedi_get_subdevice_type -- type of subdevice
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Retval: int
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Param: comedi_t * device
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Param: unsigned int subdevice
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Description:
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The function comedi_get_subdevice_type() returns an
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integer describing the type of subdevice that belongs to the comedi
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device device and has the index subdevice. The
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function returns -1 if there is an error.
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XXX Subdevice type table
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Function: comedi_find_subdevice_by_type -- search for subdevice type
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Retval: int
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Param: comedi_t * device
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Param: int type
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Param: unsigned int start_subdevice
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Description:
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The function comedi_find_subdevice_by_type() tries to
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locate a subdevice belonging to comedi device device,
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having type type, starting with the subdevice
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start_subdevice. If it finds a subdevice with the requested
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type, it returns its index. If it does not locate the requested
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subdevice, it returns -1 and sets the Comedilib error number to
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XXX "subdevice not found". If there is an error, the function
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returns -1 and sets the appropriate error.
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Function: comedi_get_subdevice_flags -- properties of subdevice
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Retval: int
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Param: comedi_t * device
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Param: unsigned int subdevice
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Description:
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This function returns a bitfield describing the capabilities of
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the specified subdevice. If there is an error, -1 is returned,
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and the Comedilib error value is set.
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XXX table.
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Function: comedi_get_n_channels -- number of subdevice channels
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Retval: int
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Param: comedi_t * device
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Param: unsigned int subdevice
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Description:
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The function comedi_get_n_channels() returns the number
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of channels of the subdevice belonging to the comedi device device
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and having index subdevice. This function returns -1 on error and
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the Comedilib error value is set.
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Function: comedi_range_is_chan_specific -- range information depends on channel
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Retval: int
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Param: comedi_t * device
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Param: unsigned int subdevice
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Description:
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If each channel of the specified subdevice has different range
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information, this function returns 1. Otherwise, this function
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returns 0. On error, this function returns -1.
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Function: comedi_maxdata_is_chan_specific -- maximum sample depends on channel
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Retval: int
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Param: comedi_t * device
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Param: unsigned int subdevice
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Description:
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If each channel of the specified subdevice has different maximum
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sample values, this function returns 1. Otherwise, this function
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returns 0. On error, this function returns -1.
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Function: comedi_get_maxdata -- maximum sample of channel
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Retval: lsampl_t
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Param: comedi_t * device
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Param: unsigned int subdevice
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Param: unsigned int channel
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Description:
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The function comedi_get_maxdata() returns the maximum
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valid data value for channel chan of subdevice
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subdevice belonging to the comedi device device
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This function returns 0 on error.
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Function: comedi_get_n_ranges -- number of ranges of channel
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Retval: int
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Param: comedi_t * device
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Param: unsigned int subdevice
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Param: unsigned int channel
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Description:
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The function comedi_get_n_ranges() returns the number
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of ranges of the channel chan belonging to the subdevice
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of the comedi device device. This function returns -1 on error.
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Function: comedi_get_range -- range information of channel
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Retval: comedi_range *
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Param: comedi_t * device
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Param: unsigned int subdevice
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Param: unsigned int channel
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Param: unsigned int range
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Description:
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The function comedi_get_range() returns a pointer to a
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comedi_range structure that contains information that can be used to
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convert sample values to or from physical units. The pointer is valid
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until the Comedi device device is closed. If there is an
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error, NULL is returned.
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Function: comedi_find_range -- search for range
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Retval: int
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Param: comedi_t * device
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Param: unsigned int subdevice
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Param: unsigned int channel
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Param: unsigned int unit
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Param: double min
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Param: double max
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Description:
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The function comedi_find_range() tries to
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locate the optimal (smallest) range for the channel chan
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belonging to a subdevice of the comedi device device,
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that includes both min and max in units.
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If a matching range is found, the index of the matching range is
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returned. If no matching range is available, the function returns
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-1.
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Function: comedi_get_buffer_size -- streaming buffer size of subdevice
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Retval: int
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Param: comedi_t * device
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Param: unsigned int subdevice
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Description:
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The function comedi_get_buffer_size() returns the size (in bytes)
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of the streaming buffer for the subdevice specified by device and
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subdevice. On error, -1 is returned.
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Function: comedi_get_max_buffer_size -- maximum streaming buffer size
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Retval: int
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Param: comedi_t * device
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Param: unsigned int subdevice
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Description:
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The function comedi_get_max_buffer_size() returns the maximum
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allowable size (in bytes) of the streaming buffer for the subdevice
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specified by device and subdevice. Changing the maximum buffer
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size requires appropriate privileges. On error, -1 is returned.
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Function: comedi_set_buffer_size -- streaming buffer size of subdevice
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Retval: int
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Param: comedi_t * device
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Param: unsigned int subdevice
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Param: unsigned int size
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Description:
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The function comedi_set_buffer_size() changes the size of the
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streaming buffer for the subdevice specified by device and subdevice.
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The parameter size must be a multiple of the virtual memory page
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size.
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The virtual memory page size can be determined using
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sysconf(_SC_PAGE_SIZE).
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Function: comedi_trigger -- perform streaming input/output (deprecated)
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Retval: int
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Param: comedi_t * device
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Param: comedi_trig * trig
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Status: deprecated
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Description:
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The function comedi_trigger() instructs Comedi to
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perform the command specified by the trigger structure trig.
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The return value depends on
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the particular trig being issued. If there is an
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error, -1 is returned.
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Function: comedi_do_insnlist -- perform multiple instructions
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Retval: int
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Param: comedi_t * device
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Param: comedi_insnlist * list
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Description:
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The function comedi_do_insnlist() performs multiple Comedi
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instructions as part of one system call. In addition, Comedi
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attempts to perform the instructions atomically, that is, on
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standard Linux kernels, no process preemption should occur
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during the instructions. However, the process may be preempted
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before or after the group of instructions.
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This function can be used to avoid the overhead of multiple
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system calls, or to ensure that multiple instructions occur
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without significant delay between them.
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Preemption may occur if any of the instructions or the data
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arrays of any of the instructions exist in non-resident or
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copy-on-write pages.
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Returns:
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The function comedi_do_insnlist() returns the number of
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sucessfully completed instructions. Error information for
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the unsucessful instruction is not available. If there is
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an error before the first instruction can be executed, -1
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is returned.
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Function: comedi_do_insn -- perform instruction
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Retval: int
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Param: comedi_t * device
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Param: comedi_insn * instruction
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Description:
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The function comedi_do_insn() performs a single instruction.
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If sucessful, comedi_do_insn() returns the number of samples
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measured, which may be less than the number of requested
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samples. Comedi limits the number of requested samples in
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order to enforce fairness among processes. If there is an
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error, -1 is returned.
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Function: comedi_lock -- subdevice reservation
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Retval: int
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Param: comedi_t * device
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Param: unsigned int subdevice
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Description:
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The function comedi_lock() reserves a subdevice for use by the
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current process. While the lock is held, no other process is
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allowed to read, write, or configure that subdevice, although
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other processes can read information about the subdevice. The
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lock is released when comedi_unlock() is called, or the device
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is closed. If sucessful, 0 is returned. If there is an error,
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-1 is returned.
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Function: comedi_unlock -- subdevice reservation
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Retval: int
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Param: comedi_t * device
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Param: unsigned int subdevice
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Description:
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The function comedi_unlock() released a subdevice lock acquired
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by comedi_lock(). If sucessful, 0 is returned, otherwise -1.
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Function: comedi_to_phys -- convert sample to physical units
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Retval: double
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Param: lsampl_t data
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Param: comedi_range * range
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Param: lsampl_t maxdata
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Description:
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Converts data given in sample values (lsampl_t, between 0 and
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maxdata) into physical units (double). The parameter range
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represents the conversion information to use, and the parameter
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maxdata represents the maximum possible data value for the
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channel that the data was read.
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Conversion of endpoint sample values, that is, sample values
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equal to 0 or maxdata, is affected by the Comedilib out-of-range
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behavior. If the out-of-range behavior is set to COMEDI_OOR_NAN,
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endpoint values are converted to NAN. If the out-of-range
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behavior is set to COMEDI_OOR_NUMBER, the endpoint values are
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converted similarly to other values.
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If there is an error, NAN is returned.
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Function: comedi_from_phys -- convert physical units to sample
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Retval: lsampl_t
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Param: double data
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Param: comedi_range * range
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Param: lsampl_t maxdata
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Description:
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Converts data given in physical units (data) into sample values
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(lsampl_t, between 0 and maxdata). The parameter rng
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represents the conversion information to use, and the parameter
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maxdata represents the maximum possible data value for the
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channel that the data will be written to.
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Conversion is not affected by out-of-range behavior. Out-of-range
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data parameters are silently truncated to the range 0 to maxdata.
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Function: comedi_data_read -- read single sample from channel
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Retval: int
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Param: comedi_t * device
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Param: unsigned int subdevice
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Param: unsigned int channel
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Param: unsigned int range
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Param: unsigned int aref
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Param: lsampl_t * data
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Description:
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Reads a single sample on the channel specified by the Comedi
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device device, the subdevice subdevice, and the channel channel.
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For the A/D conversion (if appropriate),
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the device is configured to use range specification
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range and (if appropriate) analog reference type
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aref. Analog reference types that are not supported
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by the device are silently ignored.
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The function comedi_data_read() reads one data value from
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the specified channel and places the data value in the
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location pointed to by data.
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On sucess, comedi_data_read() returns 0. If there is an
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error, -1 is returned.
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Data values returned by this function are unsigned integers
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less than or equal to the maximum sample value of the channel,
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which can be determined using the function comedi_get_maxdata().
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Conversion of data values to physical units can be performed
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by the function comedi_to_phys().
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Function: comedi_data_write -- write single sample to channel
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Retval: int
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Param: comedi_t * device
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Param: unsigned int subdevice
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Param: unsigned int channel
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Param: unsigned int range
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Param: unsigned int aref
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Param: lsampl_t data
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Description:
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Writes a single sample on the channel that is specified by the
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Comedi device device, the subdevice subdevice, and the channel
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channel. If appropriate, the device is configured to use range
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specification range and analog reference type aref. Analog
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reference types that are not supported by the device are
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silently ignored.
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The function comedi_data_write() writes the data value specified
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by the parameter data to the specified channel.
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On sucess, comedi_data_write() returns 0. If there is an error, -1 is
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returned.
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Function: comedi_dio_config -- change input/output properties of channel
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Retval: int
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Param: comedi_t * device
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Param: unsigned int subdevice
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Param: unsigned int channel
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Param: unsigned int direction
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Description:
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The function comedi_dio_config() configures individual channels
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in a digital I/O subdevice to be either input or output, depending
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on the value of parameter direction. Valid directions are
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COMEDI_INPUT or COMEDI_OUTPUT.
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Depending on the capabilities of the hardware device, multiple
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channels may be grouped together to determine direction. In this
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case, a single call to comedi_dio_config() for any channel in the
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group will affect the entire group.
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If sucessful, 0 is returned, otherwise -1.
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Function: comedi_dio_read -- read single bit from digital channel
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Retval: int
|
|
Param: comedi_t * device
|
|
Param: unsigned int subdevice
|
|
Param: unsigned int channel
|
|
Param: unsigned int * bit
|
|
Description:
|
|
The function reads the channel channel belonging to the
|
|
subdevice subdevice of device device. The data value that is
|
|
read is stored in the location pointed to by bit. This function
|
|
is equivalent to comedi_data_read(device,subdevice,channel,0,0,bit).
|
|
This function does not require a digital subdevice or a subdevice
|
|
with a maximum data value of 1 to work properly.
|
|
|
|
Return values and errors are the same as comedi_data_read().
|
|
|
|
Function: comedi_dio_write -- write single bit to digital channel
|
|
Retval: int
|
|
Param: comedi_t * device
|
|
Param: unsigned int subdevice
|
|
Param: unsigned int channel
|
|
Param: unsigned int bit
|
|
Description:
|
|
The function writes the value bit to the channel channel belonging
|
|
to the subdevice subdevice of device device. This function
|
|
is equivalent to comedi_data_write(device,subdevice,channel,0,0,bit).
|
|
This function does not require a digital subdevice or a subdevice
|
|
with a maximum data value of 1 to work properly.
|
|
|
|
Return values and errors are the same as comedi_data_write().
|
|
|
|
Function: comedi_dio_bitfield -- read/write multiple digital channels
|
|
Retval: int
|
|
Param: comedi_t * device
|
|
Param: unsigned int subdevice
|
|
Param: unsigned int write_mask
|
|
Param: unsigned int * bits
|
|
Description:
|
|
The function comedi_dio_bitfield() allows multiple channels to
|
|
be read simultaneously from a digital input or digital I/O device.
|
|
The parameter write_mask and the value pointed to by bits
|
|
are interpreted as bit fields, with the least significant bit
|
|
representing channel 0. For each bit in write_mask that is
|
|
set to 1, the cooresponding bit in *bits is written to the digital
|
|
output channel. After writing all the output channels, each
|
|
channel is read, and the result placed in the approprate bits in
|
|
*bits. The result of reading an output channel is undefined.
|
|
It is not possible to access channels greater than 31 using this
|
|
function.
|
|
|
|
Function: comedi_sv_init -- slowly-varying inputs
|
|
Retval: int
|
|
Param: comedi_sv_t * sv
|
|
Param: comedi_t * device
|
|
Param: unsigned int subdevice
|
|
Param: unsigned int channel
|
|
Description:
|
|
The function comedi_sv_init() initializes the slow varying Comedi
|
|
structure sv to use the device device, the analog input subdevice
|
|
subdevice, and the channel channel. The slow varying Comedi
|
|
structure is used by comedi_sv_measure() to accurately measure
|
|
an analog input by averaging over many samples. The default
|
|
number of samples is 100. This function returns 0 on success,
|
|
-1 on error.
|
|
|
|
Function: comedi_sv_update -- slowly-varying inputs
|
|
Retval: int
|
|
Param: comedi_sv_t * sv
|
|
Description:
|
|
The function comedi_sv_update() updates internal parameters of
|
|
the slowly varying Comedi structure sv.
|
|
|
|
Function: comedi_sv_measure -- slowly-varying inputs
|
|
Retval: int
|
|
Param: comedi_sv_t * sv
|
|
Param: double * data
|
|
Description:
|
|
The function comedi_sv_measure() uses the slowly varying Comedi
|
|
structure sv to measure a slowly varying signal. If sucessful,
|
|
the result (in physical units) is stored in the location pointed
|
|
to by data, and the number of samples is returned. On error, -1
|
|
is returned.
|
|
|
|
Function: comedi_get_cmd_src_mask -- streaming input/output capabilities
|
|
Retval: int
|
|
Param: comedi_t * device
|
|
Param: unsigned int subdevice
|
|
Param: comedi_cmd * command
|
|
Description:
|
|
The command capabilities of the subdevice indicated by the parameters
|
|
device and subdevice are probed, and the results placed in the
|
|
command structure pointed to by the parameter command. The trigger
|
|
source elements of the command structure are set to the logical OR
|
|
value of possible trigger sources. Other elements in the structure
|
|
are undefined. If sucessful, 0 is returned, otherwise -1.
|
|
|
|
Function: comedi_get_cmd_generic_timed -- streaming input/output capabilities
|
|
Retval: int
|
|
Param: comedi_t * device
|
|
Param: unsigned int subdevice
|
|
Param: comedi_cmd * command
|
|
Param: unsigned int period_ns
|
|
Description:
|
|
The command capabilities of the subdevice indicated by the parameters
|
|
device and subdevice are probed, and the results placed in the
|
|
command structure pointed to by the parameter command. The command
|
|
structure pointed to by the parameter command is modified to be a
|
|
valid command that can be used as a parameter to comedi_command().
|
|
The command measures samples at a rate that corresponds to the
|
|
period period_ns. The rate is adjusted to a rate that the device
|
|
can handle. If sucessful, 0 is returned, otherwise -1.
|
|
|
|
Function: comedi_cancel -- stop streaming input/outpu in progress
|
|
Retval: int
|
|
Param: comedi_t * device
|
|
Param: unsigned int subdevice
|
|
Description:
|
|
The function comedi_cancel() can be used to stop a Comedi command
|
|
previously started by comedi_command() that is still in progress
|
|
on the subdevice indicated by the parameters device and subdevice.
|
|
This may not return the subdevice to a ready state, since there may
|
|
be samples in the buffer that need to be read.
|
|
|
|
If sucessful, 0 is returned, otherwise -1.
|
|
|
|
Function: comedi_command -- start streaming input/output
|
|
Retval: int
|
|
Param: comedi_t * device
|
|
Param: comedi_cmd * command
|
|
Description:
|
|
The function comedi_command() starts streaming input or output. The
|
|
command structure pointed to by the parameter command specifies the
|
|
acquisition. For input subdevices, sample values are read using the
|
|
function read(). For output subdevices, sample vlaues are written
|
|
using the function write().
|
|
|
|
If sucessful, 0 is returned, otherwise -1.
|
|
|
|
Function: comedi_command_test -- test streaming input/output configuration
|
|
Retval: int
|
|
Param: comedi_t * device
|
|
Param: comedi_cmd * command
|
|
Description:
|
|
The function comedi_command_test() tests the command structure pointed
|
|
to by the parameter command and returns an integer describing the
|
|
testing stages that were sucessfully passed. In addition, if elements
|
|
of the command structure are invalid, they may be modified. Source
|
|
elements are modified to remove invalid source triggers. Argument
|
|
elements are adjusted or rounded to the nearest valid value.
|
|
|
|
XXX return values.
|
|
|
|
Function: comedi_poll -- force updating of streaming buffer
|
|
Retval: int
|
|
Param: comedi_t * device
|
|
Param: unsigned int subdevice
|
|
Description:
|
|
The function comedi_poll() is used on a subdevice that has a
|
|
Comedi command in progress in order to update the streaming buffer.
|
|
If supported by the driver, all available samples are copied to
|
|
the streaming buffer. These samples may be pending in DMA buffers
|
|
or device FIFOs. If sucessful, the number of additional bytes
|
|
available is returned. If there is an error, -1 is returned.
|
|
|
|
Function: comedi_set_max_buffer_size -- streaming buffer size of subdevice
|
|
Retval: int
|
|
Param: comedi_t * device
|
|
Param: unsigned int subdevice
|
|
Param: 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 appropriate privileges. If sucessful, the old buffer
|
|
size is returned. On error, -1 is returned.
|
|
|
|
Function: comedi_get_buffer_contents -- streaming buffer status
|
|
Retval: int
|
|
Param: comedi_t * device
|
|
Param: unsigned int subdevice
|
|
Description:
|
|
The function comedi_get_buffer_contents() is used on a subdevice
|
|
that has a Comedi command in progress. The number of bytes that
|
|
are available in the streaming buffer is returned. If there is
|
|
an error, -1 is returned.
|
|
|
|
Function: comedi_mark_buffer_read -- streaming buffer status
|
|
Retval: int
|
|
Param: comedi_t * device
|
|
Param: unsigned int subdevice
|
|
Param: unsigned int num_bytes
|
|
Description:
|
|
The function comedi_mark_buffer_read() is used on a subdevice
|
|
that has a Comedi command in progress. This function can be
|
|
used to indicate that the next num_bytes bytes in the buffer
|
|
are no longer needed and may be discarded.
|
|
If there is an error, -1 is returned.
|
|
|
|
Function: comedi_get_buffer_offset -- streaming buffer status
|
|
Retval: int
|
|
Param: comedi_t * device
|
|
Param: unsigned int subdevice
|
|
Description:
|
|
The function comedi_mark_buffer_read() is used on a subdevice
|
|
that has a Comedi command in progress. This function returns
|
|
the offset of the read pointer in the streaming buffer. This
|
|
offset is only useful for memory mapped buffers.
|
|
If there is an error, -1 is returned.
|
|
|
|
Function: comedi_get_timer -- timer information (deprecated)
|
|
Retval: int
|
|
Param: comedi_t * device
|
|
Param: unsigned int subdevice
|
|
Param: double frequency
|
|
Param: unsigned int * trigvar
|
|
Param: double * actual_frequency
|
|
Description:
|
|
Status: deprecated
|
|
The function comedi_get_timer converts the frequency frequency
|
|
to a number suitable to send to the driver in a comedi_trig
|
|
structure. This function remains for compatibility with very
|
|
old versions of Comedi, that converted sampling rates to timer
|
|
values in the libary. This conversion is now done in the kernel,
|
|
and every device has the timer type nanosec_timer, indicating
|
|
that timer values are simply a time specified in nanoseconds.
|
|
|
|
Function: comedi_timed_1chan -- streaming input (deprecated)
|
|
Retval: int
|
|
Param: comedi_t * device
|
|
Param: unsigned int subdevice
|
|
Param: unsigned int channel
|
|
Param: unsigned int range
|
|
Param: unsigned int aref
|
|
Param: double frequency
|
|
Param: unsigned int num_samples
|
|
Param: double * data
|
|
Description:
|
|
Status: deprecated
|
|
Not documented.
|
|
|
|
Function: comedi_set_global_oor_behavior -- out-of-range behavior
|
|
Retval: int
|
|
Param: enum comedi_oor_behavior behavior
|
|
Description:
|
|
Status: alpha
|
|
This function changes the Comedilib out-of-range behavior.
|
|
This currently affects the behavior of comedi_to_phys() when
|
|
converting endpoint sample values, that is, sample values
|
|
equal to 0 or maxdata. If the out-of-range behavior is set to
|
|
COMEDI_OOR_NAN, endpoint values are converted to NAN. If the
|
|
out-of-range behavior is set to COMEDI_OOR_NUMBER, the endpoint
|
|
values are converted similarly to other values.
|
|
|
|
The previous out-of-range behavior is returned.
|
|
|