/usr/share/doc/libcomedi-dev/html/x4629.html

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>Comedi: The <SPAN
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><I
CLASS="EMPHASIS"
>Control and Measurement Device Interface</I
></SPAN
>
handbook
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><DIV
CLASS="SECTION"
><H1
CLASS="SECTION"
><A
NAME="COMEDIREFERENCE"
>7. <ACRONYM
CLASS="ACRONYM"
>Comedi</ACRONYM
> Reference</A
></H1
><P
>    Reference for
  <A
HREF="x4629.html#CONSTANTSMACROS"
>constants and macros</A
>,
  <A
HREF="x4629.html#DATATYPESSTRUCTURES"
>data types and structures</A
>,
  and <A
HREF="x4629.html#FUNCTIONREFERENCE"
>functions</A
>.
  </P
><DIV
CLASS="SECTION"
><H2
CLASS="SECTION"
><A
NAME="COMEDI-COMEDILIB-H"
>7.1. Headerfiles: <TT
CLASS="FILENAME"
>comedi.h</TT
> and <TT
CLASS="FILENAME"
>comedilib.h</TT
></A
></H2
><P
>All <A
HREF="x403.html"
>application programs</A
> must
include the header file <TT
CLASS="FILENAME"
>comedilib.h</TT
>. (This file
itself includes <TT
CLASS="FILENAME"
>comedi.h</TT
>.) They contain the full
interface of <ACRONYM
CLASS="ACRONYM"
>Comedi</ACRONYM
>: defines, function prototypes, data structures.</P
><P
>The following Sections give more details.</P
></DIV
><DIV
CLASS="SECTION"
><H2
CLASS="SECTION"
><A
NAME="CONSTANTSMACROS"
>7.2. Constants and Macros</A
></H2
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="REF-MACRO-CR-PACK"
>7.2.1. CR_PACK</A
></H3
><P
>CR_PACK is used to initialize the elements of the
<CODE
CLASS="PARAMETER"
>chanlist</CODE
> array in the
<A
HREF="x4629.html#REF-TYPE-COMEDI-CMD"
>comedi_cmd</A
> data structure,
and the <CODE
CLASS="PARAMETER"
>chanspec</CODE
> member of the
<A
HREF="x4629.html#REF-TYPE-COMEDI-INSN"
>comedi_insn</A
> structure.</P
><PRE
CLASS="PROGRAMLISTING"
>#define CR_PACK(chan,rng,aref)      ( (((aref)&#38;0x3)&#60;&#60;24) | (((rng)&#38;0xff)&#60;&#60;16) | (chan) )</PRE
><P
>The <CODE
CLASS="PARAMETER"
>chan</CODE
> argument is the channel you wish to
use, with the channel numbering starting at zero.</P
><P
>The range <CODE
CLASS="PARAMETER"
>rng</CODE
> is an index, starting at zero,
whose meaning is device dependent.  The
<A
HREF="r5360.html"
>comedi_get_n_ranges()</A
>
and
<A
HREF="r5383.html"
>comedi_get_range()</A
>
functions are useful in discovering information about the available
ranges.</P
><P
>The <CODE
CLASS="PARAMETER"
>aref</CODE
> argument indicates what reference you
want the device to use.  It can be any of the following:
<P
></P
><DIV
CLASS="VARIABLELIST"
><DL
><DT
>AREF_GROUND <A
NAME="AREF-GROUND"
></A
></DT
><DD
><P
>        is for inputs/outputs referenced to ground.
      </P
></DD
><DT
>AREF_COMMON <A
NAME="AREF-COMMON"
></A
></DT
><DD
><P
>	 is for a <SPAN
CLASS="QUOTE"
>"common"</SPAN
> reference (the low inputs of all the
channels are tied together, but are isolated from ground).
      </P
></DD
><DT
>AREF_DIFF <A
NAME="AREF-DIFF"
></A
></DT
><DD
><P
>    is for differential inputs/outputs.
      </P
></DD
><DT
>AREF_OTHER <A
NAME="AREF-OTHER"
></A
></DT
><DD
><P
>    is for any reference that does not fit into the above categories.
      </P
></DD
></DL
></DIV
>
Particular drivers may or may not use the AREF flags.  If they are
not supported, they are silently ignored.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="REF-MACRO-RANGE-LENGTH"
>7.2.2. RANGE_LENGTH (deprecated)</A
></H3
><P
>Rangetype values are library-internal tokens that represent an
array of range information structures.  These numbers are primarily
used for communication between the kernel and library.</P
><P
>The RANGE_LENGTH() macro returns the length of the array that is
specified by the rangetype token.</P
><P
>The RANGE_LENGTH() macro is deprecated, and should not be used in
new applications.  It is scheduled to be removed from the header
file at version 1.0.  Binary compatibility may be broken for version
1.1.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="REF-ENUM-COMEDI-CONVERSION-DIRECTION"
>7.2.3. enum comedi_conversion_direction</A
></H3
><P
><PRE
CLASS="PROGRAMLISTING"
>enum comedi_conversion_direction
{
	COMEDI_TO_PHYSICAL,
	COMEDI_FROM_PHYSICAL
};</PRE
></P
><P
>A comedi_conversion_direction is used to choose between converting data
from Comedi's integer sample values to a physical value (COMEDI_TO_PHYSICAL),
and converting from a physical value to Comedi's integer sample values (COMEDI_FROM_PHYSICAL).</P
></DIV
></DIV
><DIV
CLASS="SECTION"
><H2
CLASS="SECTION"
><A
NAME="DATATYPESSTRUCTURES"
>7.3. Data Types and Structures</A
></H2
><P
>This Section explains the data structures that users of the <ACRONYM
CLASS="ACRONYM"
>Comedi</ACRONYM
>
API are confronted with:
<PRE
CLASS="PROGRAMLISTING"
>typedef struct subdevice_struct       <A
HREF="x4629.html#REF-TYPE-SUBDEVICE-STRUCT"
>subdevice_struct</A
>:
typedef struct comedi_devinfo_struct  <A
HREF="x4629.html#REF-TYPE-COMEDI-DEVINFO"
>comedi_devinfo</A
>;
typedef struct comedi_t_struct        <A
HREF="x4629.html#REF-TYPE-COMEDI-T"
>comedi_t</A
>;
typedef struct sampl_t_struct         <A
HREF="x4629.html#REF-TYPE-SAMPL-T"
>sampl_t</A
>;
typedef struct lsampl_t_struct        <A
HREF="x4629.html#REF-TYPE-LSAMPL-T"
>lsampl_t</A
>;
typedef struct comedi_sv_t_struct     <A
HREF="x4629.html#REF-TYPE-COMEDI-SV-T"
>comedi_sv_t</A
>;
typedef struct comedi_cmd_struct      <A
HREF="x4629.html#REF-TYPE-COMEDI-CMD"
>comedi_cmd</A
>;
typedef struct comedi_insn_struct     <A
HREF="x4629.html#REF-TYPE-COMEDI-INSN"
>comedi_insn</A
>;
typedef struct comedi_range_struct    <A
HREF="x4629.html#REF-TYPE-COMEDI-RANGE"
>comedi_range</A
>;
typedef struct comedi_krange_struct   <A
HREF="x4629.html#REF-TYPE-COMEDI-KRANGE"
>comedi_krange</A
>;
typedef struct comedi_insnlist_struct <A
HREF="x4629.html#REF-TYPE-COMEDI-INSNLIST"
>comedi_insnlist</A
>;</PRE
>
The data structures used in the implementation of the <ACRONYM
CLASS="ACRONYM"
>Comedi</ACRONYM
> drivers
are treated <A
HREF="x1394.html#DRIVERDATASTRUCTURES"
>elsewhere</A
>.</P
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="REF-TYPE-SUBDEVICE-STRUCT"
>7.3.1. subdevice_struct</A
></H3
><P
>The data type <CODE
CLASS="PARAMETER"
>subdevice_struct</CODE
> is used to store
information about a subdevice. This structure is usually filled in
automatically when the driver is loaded (<SPAN
CLASS="QUOTE"
>"attached"</SPAN
>), so
programmers need not access this data structure directly.
<PRE
CLASS="PROGRAMLISTING"
>typedef struct subdevice_struct <A
NAME="REF-TYPE-SUBDEVICE"
></A
>subdevice;

struct subdevice_struct{
  unsigned int type;
  unsigned int n_chan;
  unsigned int subd_flags;
  unsigned int timer_type;
  unsigned int len_chanlist;
  <A
HREF="x4629.html#REF-TYPE-LSAMPL-T"
>lsampl_t</A
> maxdata;
  unsigned int flags;
  unsigned int range_type;

  <A
HREF="x4629.html#REF-TYPE-LSAMPL-T"
>lsampl_t</A
> *maxdata_list;
  unsigned int *range_type_list;
  unsigned int *flags_list;

  <A
HREF="x4629.html#REF-TYPE-COMEDI-RANGE"
>comedi_range</A
> *rangeinfo;
  <A
HREF="x4629.html#REF-TYPE-COMEDI-RANGE"
>ccomedi_range</A
> **rangeinfo_list;

  unsigned int has_cmd;
  unsigned int has_insn_bits;

  int cmd_mask_errno;
  <A
HREF="x4629.html#REF-TYPE-COMEDI-CMD"
>comedi_cmd</A
> *cmd_mask;
  int cmd_timed_errno;
  <A
HREF="x4629.html#REF-TYPE-COMEDI-CMD"
>comedi_cmd</A
> *cmd_timed;
};</PRE
>&#13;</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="REF-TYPE-COMEDI-DEVINFO"
>7.3.2. comedi_devinfo</A
></H3
><P
>The data type <CODE
CLASS="PARAMETER"
>comedi_devinfo</CODE
> is used to store
information about a device. This structure is usually filled in
automatically when the driver is loaded (<SPAN
CLASS="QUOTE"
>"attached"</SPAN
>), so
programmers need not access this data structure directly.
<PRE
CLASS="PROGRAMLISTING"
>typedef struct comedi_devinfo_struct comedi_devinfo;

struct comedi_devinfo_struct{
  unsigned int version_code;    // version number of the Comedi code
  unsigned int n_subdevs;       // number of subdevices on this device
  char         driver_name[COMEDI_NAMELEN];
  char         board_name[COMEDI_NAMELEN];
  int          read_subdevice;  // index of subdevice whose buffer is read by read(), etc. on file descriptor from comedi_fileno() (negative means none)
  int          write_subdevice; // index of subdevice whose buffer is written by write(), etc. on file descriptor from comedi_fileno() (negatove means none).
  int          unused[30];
};&#13;</PRE
></P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="REF-TYPE-COMEDI-T"
>7.3.3. comedi_t</A
></H3
><P
>The data type <CODE
CLASS="PARAMETER"
>comedi_t</CODE
> is used to represent an
open <ACRONYM
CLASS="ACRONYM"
>Comedi</ACRONYM
> device:
<PRE
CLASS="PROGRAMLISTING"
>typedef struct comedi_t_struct comedi_t;

struct comedi_t_struct{
  int magic;        // driver-specific magic number, for identification
  int fd;           // file descriptor, for open() and close()
  int n_subdevices; // number of subdevices on this device
  <A
HREF="x4629.html#REF-TYPE-COMEDI-DEVINFO"
>comedi_devinfo</A
> devinfo;
  <A
HREF="x4629.html#REF-TYPE-SUBDEVICE"
>subdevice</A
> *subdevices; // pointer to subdevice list
                         // filled in automatically at load time
  unsigned int has_insnlist_ioctl; // can process <A
HREF="x621.html#ANCHOR.INSTRUCTION.LIST"
>instruction lists</A
>
  unsigned int has_insn_ioctl;     // can process <A
HREF="x621.html#INSTRUCTIONS"
>instructions</A
>
};</PRE
>
A valid <CODE
CLASS="PARAMETER"
>comedi_t</CODE
> pointer is returned by a
successful call to
<A
HREF="r4857.html"
>comedi_open()</A
>,
and should be used for subsequent access to the device.
It is a transparent type, and pointers to type
<CODE
CLASS="PARAMETER"
>comedi_t</CODE
>
should not be dereferenced by the application.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="REF-TYPE-SAMPL-T"
>7.3.4. sampl_t</A
></H3
><PRE
CLASS="PROGRAMLISTING"
>typedef unsigned short sampl_t;</PRE
><P
>The data type <A
HREF="x4629.html#REF-TYPE-SAMPL-T"
>sampl_t</A
> is one
of the generic
types used to represent data values in Comedilib.  It is used in a few
places where a data type
shorter than <A
HREF="x4629.html#REF-TYPE-LSAMPL-T"
>lsampl_t</A
> is
useful.  On most architectures,
<A
HREF="x4629.html#REF-TYPE-SAMPL-T"
>sampl_t</A
>
is defined to be <CODE
CLASS="PARAMETER"
>uint16</CODE
>.</P
><P
>Most drivers represent data transferred by <CODE
CLASS="FUNCTION"
>read()</CODE
> and
<CODE
CLASS="FUNCTION"
>write()</CODE
> using
<A
HREF="x4629.html#REF-TYPE-SAMPL-T"
>sampl_t</A
>.
Applications should check the subdevice flag
SDF_LSAMPL to determine if the subdevice uses
<A
HREF="x4629.html#REF-TYPE-SAMPL-T"
>sampl_t</A
> or
<A
HREF="x4629.html#REF-TYPE-LSAMPL-T"
>lsampl_t</A
>.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="REF-TYPE-LSAMPL-T"
>7.3.5. lsampl_t</A
></H3
><PRE
CLASS="PROGRAMLISTING"
>typedef unsigned int lsampl_t;</PRE
><P
>The data type
<A
HREF="x4629.html#REF-TYPE-LSAMPL-T"
>lsampl_t</A
>
is the data type typically used to represent
data values in libcomedi.  On most architectures,
<A
HREF="x4629.html#REF-TYPE-LSAMPL-T"
>lsampl_t</A
>
is defined to be uint32.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="REF-TYPE-COMEDI-TRIG"
>7.3.6. comedi_trig (deprecated)</A
></H3
><PRE
CLASS="PROGRAMLISTING"
>typedef struct comedi_trig_struct comedi_trig;

struct comedi_trig_struct{
  unsigned int subdev;   /* subdevice */
  unsigned int mode;  /* mode */
  unsigned int flags;
  unsigned int n_chan;  /* number of channels */
  unsigned int *chanlist;   /* channel/range list */
  <A
HREF="x4629.html#REF-TYPE-SAMPL-T"
>sampl_t</A
> *data;  /* data list, size depends on subd flags */
  unsigned int n;  /* number of scans */
  unsigned int trigsrc;
  unsigned int trigvar;
  unsigned int trigvar1;
  unsigned int data_len;
  unsigned int unused[3];
};</PRE
><P
>The comedi_trig structure is a control structure used by the
COMEDI_TRIG ioctl, an older method of communicating
instructions to the driver and hardware.  Use of comedi_trig is
deprecated, and should not be used in new applications.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="REF-TYPE-COMEDI-SV-T"
>7.3.7. comedi_sv_t</A
></H3
><PRE
CLASS="PROGRAMLISTING"
>typedef struct comedi_sv_struct comedi_sv_t;

struct comedi_sv_struct{
  comedi_t *dev;
  unsigned int subdevice;
  unsigned int chan;

  /* range policy */
  int range;
  int aref;

  /* number of measurements to average (for ai) */
  int n;

  <A
HREF="x4629.html#REF-TYPE-LSAMPL-T"
>lsampl_t</A
> maxdata;
};</PRE
><P
>The comedi_sv_t structure is used by the comedi_sv_*()
functions to provide a simple method of accurately measuring
slowly varying inputs.  See the relevant section for more
details.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="REF-TYPE-COMEDI-CMD"
>7.3.8. comedi_cmd</A
></H3
><PRE
CLASS="PROGRAMLISTING"
>typedef struct comedi_cmd_struct comedi_cmd;

struct comedi_cmd_struct{
  unsigned int subdev;
  unsigned int flags;

  unsigned int start_src;
  unsigned int start_arg;

  unsigned int scan_begin_src;
  unsigned int scan_begin_arg;

  unsigned int convert_src;
  unsigned int convert_arg;

  unsigned int scan_end_src;
  unsigned int scan_end_arg;

  unsigned int stop_src;
  unsigned int stop_arg;

  unsigned int *chanlist;
  unsigned int chanlist_len;

  <A
HREF="x4629.html#REF-TYPE-SAMPL-T"
>sampl_t</A
> *data;
  unsigned int data_len;
};</PRE
><P
>More information on using commands can be found in the
command section.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="REF-TYPE-COMEDI-INSN"
>7.3.9. comedi_insn</A
></H3
><PRE
CLASS="PROGRAMLISTING"
>typedef struct comedi_insn_struct comedi_insn;

struct comedi_insn_struct{
  unsigned int insn;
  unsigned int n;
  <A
HREF="x4629.html#REF-TYPE-LSAMPL-T"
>lsampl_t</A
>*data;
  unsigned int subdev;
  unsigned int chanspec;
  unsigned int unused[3];
};</PRE
><P
>Comedi instructions are described by the comedi_insn structure.
Applications send instructions to the driver in order to perform
control and measurement operations that are done immediately or
synchronously, i.e., the operations complete before program control
returns to the application.  In particular, instructions cannot
describe acquisition that involves timers or external events.</P
><P
>The field insn determines the type of instruction that is sent
to the driver. Valid instruction types are:</P
><P
></P
><DIV
CLASS="VARIABLELIST"
><DL
><DT
><A
NAME="INSN-READ"
></A
>
INSN_READ</DT
><DD
><P
>read values from an input channel
      </P
></DD
><DT
><A
NAME="INSN-WRITE"
></A
>
INSN_WRITE</DT
><DD
><P
>write values to an output channel
      </P
></DD
><DT
><A
NAME="INSN-BITS"
></A
>
INSN_BITS</DT
><DD
><P
>read/write values on multiple digital I/O channels
      </P
></DD
><DT
><A
NAME="INSN-CONFIG"
></A
>
INSN_CONFIG</DT
><DD
><P
>configure a subdevice
      </P
></DD
><DT
><A
NAME="INSN-GTOD"
></A
>
INSN_GTOD</DT
><DD
><P
>read a timestamp, identical to gettimeofday()
      </P
></DD
><DT
><A
NAME="INSN-WAIT"
></A
>
INSN_WAIT</DT
><DD
><P
>wait a specified number of nanoseconds
      </P
></DD
></DL
></DIV
><P
>The number of samples to read or write, or the size of the configuration
structure is specified by the field n, and the buffer for those
samples by data.  The field subdev is the subdevice index
that the instruction is sent to.  The field chanspec specifies
the channel, range, and analog reference (if applicable).</P
><P
>Instructions can be sent to drivers using comedi_do_insn().
Multiple instructions can be sent to drivers in the same system
call using comedi_do_insnlist().</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="REF-TYPE-COMEDI-RANGE"
>7.3.10. comedi_range</A
></H3
><PRE
CLASS="PROGRAMLISTING"
>typedef struct comedi_range_struct comedi_range;

struct comedi_range_struct{
  double min;
  double max;
  unsigned int unit;
}comedi_range;</PRE
><P
>The comedi_range structure conveys part of the information
necessary to translate sample values to physical units, in particular,
the endpoints of the range and the physical unit type.  The
physical unit type is specified by the field unit, which may
take the values UNIT_volt for volts, UNIT_mA for milliamps,
or UNIT_none for unitless.  The endpoints are specified by
the fields min and max.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="REF-TYPE-COMEDI-KRANGE"
>7.3.11. comedi_krange</A
></H3
><PRE
CLASS="PROGRAMLISTING"
>typedef struct comedi_krange_struct comedi_krange;

struct comedi_krange_struct{
  int min;
  int max;
  unsigned int flags;
};</PRE
><P
>The comedi_krange structure is used to transfer range information
between the driver and Comedilib, and should not normally be used
by applications.  The structure conveys the same information as the
comedi_range structure, except the fields min and max
are integers, multiplied by a factor of 1000000 compared to the
counterparts in comedi_range.</P
><P
>In addition, kcomedilib uses the comedi_krange structure in place
of the comedi_range structure.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="REF-TYPE-COMEDI-INSNLIST"
>7.3.12. comedi_insnlist</A
></H3
><PRE
CLASS="PROGRAMLISTING"
>typedef struct comedi_insnlist_struct comedi_insnlist;

struct comedi_insnlist_struct{
  unsigned int n_insns;
  comedi_insn *insns;
};</PRE
><P
>An instruction list (insnlist) structure is used to communicate
a list of instructions.</P
></DIV
></DIV
><DIV
CLASS="SECTION"
><H2
CLASS="SECTION"
><A
NAME="FUNCTIONREFERENCE"
>7.4. Comedi Function Reference</A
></H2
><DIV
CLASS="TOC"
><DL
><DT
><B
>Table of Contents</B
></DT
><DT
><A
HREF="r4835.html"
>comedi_close</A
>&nbsp;--&nbsp;close a Comedi device</DT
><DT
><A
HREF="r4857.html"
>comedi_open</A
>&nbsp;--&nbsp;open a Comedi device</DT
><DT
><A
HREF="r4879.html"
>comedi_loglevel</A
>&nbsp;--&nbsp;change Comedilib logging properties</DT
><DT
><A
HREF="r4909.html"
>comedi_perror</A
>&nbsp;--&nbsp;print a Comedilib error message</DT
><DT
><A
HREF="r4930.html"
>comedi_strerror</A
>&nbsp;--&nbsp;return string describing Comedilib error code</DT
><DT
><A
HREF="r4951.html"
>comedi_errno</A
>&nbsp;--&nbsp;number of last Comedilib error</DT
><DT
><A
HREF="r4973.html"
>comedi_fileno</A
>&nbsp;--&nbsp;integer descriptor of Comedilib device</DT
><DT
><A
HREF="r4992.html"
>comedi_get_n_subdevices</A
>&nbsp;--&nbsp;number of subdevices</DT
><DT
><A
HREF="r5011.html"
>comedi_get_version_code</A
>&nbsp;--&nbsp;Comedi version code</DT
><DT
><A
HREF="r5032.html"
>comedi_get_driver_name</A
>&nbsp;--&nbsp;Comedi driver name</DT
><DT
><A
HREF="r5051.html"
>comedi_get_board_name</A
>&nbsp;--&nbsp;Comedi device name</DT
><DT
><A
HREF="r5070.html"
>comedi_get_subdevice_type</A
>&nbsp;--&nbsp;type of subdevice</DT
><DT
><A
HREF="r5092.html"
>comedi_find_subdevice_by_type</A
>&nbsp;--&nbsp;search for subdevice type</DT
><DT
><A
HREF="r5115.html"
>comedi_get_read_subdevice</A
>&nbsp;--&nbsp;find streaming input subdevice</DT
><DT
><A
HREF="r5134.html"
>comedi_get_write_subdevice</A
>&nbsp;--&nbsp;find streaming output subdevice</DT
><DT
><A
HREF="r5153.html"
>comedi_get_subdevice_flags</A
>&nbsp;--&nbsp;properties of subdevice</DT
><DT
><A
HREF="r5268.html"
>comedi_get_n_channels</A
>&nbsp;--&nbsp;number of subdevice channels</DT
><DT
><A
HREF="r5289.html"
>comedi_range_is_chan_specific</A
>&nbsp;--&nbsp;range information depends on channel</DT
><DT
><A
HREF="r5310.html"
>comedi_maxdata_is_chan_specific</A
>&nbsp;--&nbsp;maximum sample depends on channel</DT
><DT
><A
HREF="r5331.html"
>comedi_get_maxdata</A
>&nbsp;--&nbsp;maximum sample of channel</DT
><DT
><A
HREF="r5360.html"
>comedi_get_n_ranges</A
>&nbsp;--&nbsp;number of ranges of channel</DT
><DT
><A
HREF="r5383.html"
>comedi_get_range</A
>&nbsp;--&nbsp;range information of channel</DT
><DT
><A
HREF="r5408.html"
>comedi_find_range</A
>&nbsp;--&nbsp;search for range</DT
><DT
><A
HREF="r5437.html"
>comedi_get_buffer_size</A
>&nbsp;--&nbsp;streaming buffer size of subdevice</DT
><DT
><A
HREF="r5458.html"
>comedi_get_max_buffer_size</A
>&nbsp;--&nbsp;maximum streaming buffer size</DT
><DT
><A
HREF="r5479.html"
>comedi_set_buffer_size</A
>&nbsp;--&nbsp;streaming buffer size of subdevice</DT
><DT
><A
HREF="r5503.html"
>comedi_trigger</A
>&nbsp;--&nbsp;perform streaming input/output (deprecated)</DT
><DT
><A
HREF="r5527.html"
>comedi_do_insnlist</A
>&nbsp;--&nbsp;perform multiple instructions</DT
><DT
><A
HREF="r5553.html"
>comedi_do_insn</A
>&nbsp;--&nbsp;perform instruction</DT
><DT
><A
HREF="r5574.html"
>comedi_lock</A
>&nbsp;--&nbsp;subdevice reservation</DT
><DT
><A
HREF="r5598.html"
>comedi_unlock</A
>&nbsp;--&nbsp;subdevice reservation</DT
><DT
><A
HREF="r5619.html"
>comedi_to_phys</A
>&nbsp;--&nbsp;convert sample to physical units</DT
><DT
><A
HREF="r5644.html"
>comedi_to_physical</A
>&nbsp;--&nbsp;convert sample to physical units</DT
><DT
><A
HREF="r5673.html"
>comedi_from_phys</A
>&nbsp;--&nbsp;convert physical units to sample</DT
><DT
><A
HREF="r5697.html"
>comedi_from_physical</A
>&nbsp;--&nbsp;convert physical units to sample</DT
><DT
><A
HREF="r5725.html"
>comedi_data_read</A
>&nbsp;--&nbsp;read single sample from channel</DT
><DT
><A
HREF="r5758.html"
>comedi_data_read_delayed</A
>&nbsp;--&nbsp;read single sample from channel after delaying for specified settling time</DT
><DT
><A
HREF="r5790.html"
>comedi_data_read_hint</A
>&nbsp;--&nbsp;tell driver which channel/range/aref you are going to read from next</DT
><DT
><A
HREF="r5818.html"
>comedi_data_write</A
>&nbsp;--&nbsp;write single sample to channel</DT
><DT
><A
HREF="r5849.html"
>comedi_dio_config</A
>&nbsp;--&nbsp;change input/output properties of channel</DT
><DT
><A
HREF="r5876.html"
>comedi_dio_get_config</A
>&nbsp;--&nbsp;query input/output properties of channel</DT
><DT
><A
HREF="r5903.html"
>comedi_dio_read</A
>&nbsp;--&nbsp;read single bit from digital channel</DT
><DT
><A
HREF="r5929.html"
>comedi_dio_write</A
>&nbsp;--&nbsp;write single bit to digital channel</DT
><DT
><A
HREF="r5955.html"
>comedi_dio_bitfield</A
>&nbsp;--&nbsp;read/write multiple digital channels</DT
><DT
><A
HREF="r5983.html"
>comedi_dio_bitfield2</A
>&nbsp;--&nbsp;read/write multiple digital channels</DT
><DT
><A
HREF="r6018.html"
>comedi_sv_init</A
>&nbsp;--&nbsp;slowly-varying inputs</DT
><DT
><A
HREF="r6046.html"
>comedi_sv_update</A
>&nbsp;--&nbsp;slowly-varying inputs</DT
><DT
><A
HREF="r6068.html"
>comedi_sv_measure</A
>&nbsp;--&nbsp;slowly-varying inputs</DT
><DT
><A
HREF="r6092.html"
>comedi_get_cmd_src_mask</A
>&nbsp;--&nbsp;streaming input/output capabilities</DT
><DT
><A
HREF="r6115.html"
>comedi_get_cmd_generic_timed</A
>&nbsp;--&nbsp;streaming input/output capabilities</DT
><DT
><A
HREF="r6142.html"
>comedi_cancel</A
>&nbsp;--&nbsp;stop streaming input/output in progress</DT
><DT
><A
HREF="r6164.html"
>comedi_command</A
>&nbsp;--&nbsp;start streaming input/output</DT
><DT
><A
HREF="r6186.html"
>comedi_command_test</A
>&nbsp;--&nbsp;test streaming input/output configuration</DT
><DT
><A
HREF="r6214.html"
>comedi_poll</A
>&nbsp;--&nbsp;force updating of streaming buffer</DT
><DT
><A
HREF="r6235.html"
>comedi_set_max_buffer_size</A
>&nbsp;--&nbsp;streaming buffer size of subdevice</DT
><DT
><A
HREF="r6258.html"
>comedi_get_buffer_contents</A
>&nbsp;--&nbsp;streaming buffer status</DT
><DT
><A
HREF="r6279.html"
>comedi_mark_buffer_read</A
>&nbsp;--&nbsp;streaming buffer control</DT
><DT
><A
HREF="r6302.html"
>comedi_mark_buffer_written</A
>&nbsp;--&nbsp;streaming buffer control</DT
><DT
><A
HREF="r6325.html"
>comedi_get_buffer_offset</A
>&nbsp;--&nbsp;streaming buffer status</DT
><DT
><A
HREF="r6346.html"
>comedi_get_timer</A
>&nbsp;--&nbsp;timer information (deprecated)</DT
><DT
><A
HREF="r6376.html"
>comedi_timed_1chan</A
>&nbsp;--&nbsp;streaming input (deprecated)</DT
><DT
><A
HREF="r6412.html"
>comedi_set_global_oor_behavior</A
>&nbsp;--&nbsp;out-of-range behavior</DT
><DT
><A
HREF="r6435.html"
>comedi_apply_calibration</A
>&nbsp;--&nbsp;set hardware calibration from file</DT
><DT
><A
HREF="r6475.html"
>comedi_apply_parsed_calibration</A
>&nbsp;--&nbsp;set calibration from memory</DT
><DT
><A
HREF="r6512.html"
>comedi_cleanup_calibration_file</A
>&nbsp;--&nbsp;free calibration resources</DT
><DT
><A
HREF="r6535.html"
>comedi_get_default_calibration_path</A
>&nbsp;--&nbsp;get default calibration file path</DT
><DT
><A
HREF="r6561.html"
>comedi_parse_calibration_file</A
>&nbsp;--&nbsp;load contents of calibration file</DT
><DT
><A
HREF="r6587.html"
>comedi_get_hardcal_converter</A
>&nbsp;--&nbsp;get converter for hardware-calibrated subdevice</DT
><DT
><A
HREF="r6633.html"
>comedi_get_softcal_converter</A
>&nbsp;--&nbsp;get converter for software-calibrated subdevice</DT
></DL
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libcomedi-dev 0.8.1-5ubuntu6 / usr / share / doc / libcomedi-dev / html / x4629.html
