stv0g/comedilib
1
0
Fork 0
Code Issues Pull requests Releases Wiki Activity

Additional typing

Browse source
This commit is contained in:
David Schleef 2001-10-04 20:10:36 +00:00
parent a6f0492b24
commit 380f2fc1eb
1 changed files with 116 additions and 26 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

142
doc/comedilib.sgml
View file

@ -786,6 +786,7 @@ access to the device.
It is a transparent type, and pointers to type <tt/comedi_t/
should not be dereferenced by the application.
<p>Source: <tt>/include/comedi.h</tt>
<p>
<sect2>sampl_t
@ -793,20 +794,29 @@ should not be dereferenced by the application.
<p>
The data type <tt/sampl_t/ is one of the generic types used to represent
data values in libcomedi. It is used in a few places where a shorter
data type is useful, but is limited to 16 bits on the i386 architecture.
data values in libcomedi. It is used in a few places where a data type
shorter than <tt/lsampl_t/ is useful. On most architectures, <tt/sampl_t/
is defined to be <tt/uint16/.
<p>
Most drivers represent data trasferred by <tt/read()/ and <tt/write()/
using <tt/sampl_t/. Applications should check the subdevice flag
<tt/SDF_LSAMPL/ to determine if the subdevice uses <tt/sampl_t/ or
<tt/lsampl_t/.
<p>Source: <tt>/include/comedi.h</tt>
<p>
<sect2>lsampl_t
<label id="lsampl_t">
<p>
The data type <tt/lsampl_t/ is one of the generic types used to represent
data values in libcomedi. It is currently defined to be <tt/unsigned int/.
The data type <tt/lsampl_t/ is the data type typically used to represent
data values in libcomedi. On most architectures, <tt/lsampl_t/ is
defined to be <tt/uint32/.
<p>Source: <tt>/include/comedi.h</tt>
<p>
<sect2>comedi_trig_struct <it/(deprecated)/
@ -837,8 +847,7 @@ 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>
This structure is defined as part of the Comedi kernel interface.
<p>Source: <tt>/include/comedi.h</tt>
<p>
<sect2>comedi_sv_t
@ -867,6 +876,7 @@ functions to provide a simple method of accurately measuring
slowly varying inputs. See the relevant section for more
details.
<p>Source: <tt>comedilib.h</tt>
<p>
<sect2>comedi_cmd
@ -907,31 +917,111 @@ struct comedi_cmd_struct{
More information on using commands can be found in the
<ref id="command_section" name="command"> section.
<p>
This structure is defined as part of the Comedi kernel interface.
<p>Source: <tt>comedilib.h</tt>
<p>
<sect2>comedi_insn
<label id="comedi_insn">
<p>
undocumented
<tscreen><verb>
typedef struct comedi_insn_struct comedi_insn;
struct comedi_insn_struct{
unsigned int insn;
unsigned int n;
lsampl_t *data;
unsigned int subdev;
unsigned int chanspec;
unsigned int unused[3];
};
</verb></tscreen>
<p>
Related functions are described in section XXX.
Comedi instructions are described by the <tt/comedi_insn/ structure.
Applications send instructions to the driver in order to preform
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>
This structure is defined as part of the Comedi kernel interface.
The field <tt/insn/ determines the type of instruction that is sent
to the driver. Valid instruction types are
<itemize>
<item>INSN_READ read values from an input channel
<item>INSN_WRITE write values to an output channel
<item>INSN_BITS read/write values on multiple digital I/O channels
<item>INSN_CONFIG configure a subdevice
<item>INSN_GTOD read a timestamp, identical to <tt/gettimeofday()/
<item>INSN_WAIT wait a specified number of nanoseconds
</itemize>
<p>
The number of samples to read or write, or the size of the configuration
structure is specified by the field <tt/n/, and the buffer for those
samples by <tt/data/. The field <tt/subdev/ is the subdevice index
that the instruction is sent to. The field <tt/chanspec/ specifies
the channel, range, and analog reference (if applicable).
<p>
Instructions can be sent to drivers using <tt/comedi_do_insn()/.
Multiple instructions can be sent to drivers in the same system
call using <tt/comedi_do_insnlist()/.
<p>Source: <tt>comedi.h</tt>
<p>
<sect2>comedi_range
<label id="comedi_range">
<p>
undocumented
<tscreen><verb>
typedef struct{
double min;
double max;
unsigned int unit;
}comedi_range;
</verb></tscreen>
<p>
The <tt/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 <tt/unit/, which may
take the values <tt/UNIT_volt/ for volts, <tt/UNIT_mA/ for milliamps,
or <tt/UNIT_none/ for unitless. The endpoints are specified by
the fields <tt/min/ and <tt/max/.
<p>
XXX RF_EXTERNAL
<p>Source: <tt>comedilib.h</tt>
<p>
<sect2>comedi_krange
<label id="comedi_krange">
<p>
<tscreen><verb>
struct comedi_krange_struct{
int min;
int max;
unsigned int flags;
};
</verb></tscreen>
<p>
The <tt/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
<tt/comedi_range/ structure, except the fields <tt/min/ and <tt/max/
are integers, multiplied by a factor of 1000000 compared to the
counterparts in <tt/comedi_range/.
<p>Source: <tt>comedi.h</tt>
<sect1>Functions
<p>
@ -1112,11 +1202,6 @@ set, the cooresponding bit in <tt/*bits/ is written to the digital
output channel. Each digital input channel is read, and the result
placed in the approprate bits in <tt/*bits/.
<p>
The current implementation reads and writes bits using separate
system calls, which is not ideal. When the kernel driver supports
simultaneous reading/writing, this will be fixed in the library.
<p>
It should be noted that it is not possible to access channels
greater than 31 using this function.
@ -1157,7 +1242,7 @@ chan,unsigned int *bit);/
<p>
The function reads the status of channel <tt/chan/ belonging to the digital
input subdevice <tt/subd/ of device <tt/it/. The result, 0 or 1, is stored
in bit. Returns -1 on failure.
in <tt/bit/. Returns -1 on failure.
<p>
This function is equivalent to <tt/comedi_data_read(it,subd,chan,0,0,bit)/.
@ -1176,6 +1261,9 @@ The function writes the value of <tt/bit/, 0 or 1, to channel <tt/chan/,
belonging to the digital output device <tt/subd/ of device <tt/it/. Returns
-1 on failure.
<p>
This function is equivalent to <tt/comedi_data_write(it,subd,chan,0,0,bit)/.
<p>
Source: <tt>/lib/dio.c</tt>
@ -1183,14 +1271,15 @@ Source: <tt>/lib/dio.c</tt>
<sect2>comedi_fileno()
<p>
<tt/int comedi_fileno(comedi_t *it);/
<tt/int comedi_fileno(comedi_t *dev);/
<p>
The function <tt/comedi_fileno/
returns the integer descriptor for the handle <tt/it/. It
is equivalent to the standard function <tt/fileno/. If
<tt>it</tt> is an invalid <tt>comedi_t</tt> pointer, the function
returns -1 and sets the appropriate libcomedi error value.
returns the integer descriptor for the device <tt/dev/. It
is functionally similar to the standard C library function
<tt/fileno()/. If <tt>dev</tt> is an invalid <tt>comedi_t</tt>
pointer, the function returns -1 and sets the appropriate
libcomedi error value.
Source: <tt>/lib/comedi.c</tt>
@ -1207,8 +1296,9 @@ The function <tt/comedi_find_range/ tries to
locate the optimal (smallest) range for the channel <tt>chan</tt>
belonging to a <tt>subdevice</tt> of the comedi device <tt>it</tt>,
that includes both <tt>min</tt> and <tt>max</tt> in <tt>units</tt>.
If it finds a matching range, it returns its index. If no
matching range is available, it returns -1.
If a matching range is found, the index of the matching range is
returned. If no matching range is available, the function returns
-1.
<p>
Valid units are: