KNOWN ISSUES:
- When sampling with 100 NPLC, the poll function will timeout a few
times before the first sample is acquired. Increasing the timeout
passed to sr_scpi_source_add() will cause all the other commands to
be processed slowly, producing a sampling rate of about one sample
every ten seconds.
- Support for plug-in cards (44491A and 44492A) is not implemented.
- Support for AC, AC+DC and four-wire resistance measurements is not
implemented.
- Support for configuring the frequency measurement source is not
implemented.
High precision multimeters have a special setting, called "number of
powerline cycles" (NPLC) which determines the integration time of the
ADC in terms of the power line period. Some devices need their NPLC
adjusted from the default value before they can measure at their full
rated precision.
Devices connected on a real GPIB bus are placed in remote mode when
opening them. libgpib does not automatically place devices back in
local mode when closing the handle. It is thus possible to lock out a
GPIB device by probing it with libsigrok.
This happens on the HP 3457A meter, which does not have a "LOCAL"
command, and must be put back in local mode via GPIB handshake.
ibloc() takes care of this, and it does it on a per-device basis,
such that other devices on the GPIB bus are not affected.
libgpib has an error_string which formats a numeric error code into a
human-readable description. Use that instead of printing the numeric
code, as it makes debugging easier.
- Don't set capturefile if no logic channels are saved
- Don't set total probes if no logic channels are saved
- Save analog channels without index gaps (e.g. probe1/probe4)
Note: This commit is based on the initial implementation by
Christer Ekholm (but stashed into one commit), with some adaptations
(forward porting, coding style and consistency fixes) by Uwe Hermann.
We want the size of the struct, not of a pointer to the struct. And to
be absolutely future proof, dereference the pointer we are assigning the
memory to (not the one we are copying the data from). Found by Coverity,
CID 50858.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The firmware has "on\n" and "off\n" commands since 1.10, so use them.
Apparently you can only set the state (on/off) of the load, but it's
not possible to query the current state.
Also note that the __ namespace is reserved by POSIX for its private
usage, so user land software should never rely on any kind of API
with a __ prefix.
The last release (0.3.0) had the libtool version (current:revision:age)
set to 2:0:0. Since this release adds, removes, and changes interfaces,
the new version is 3:0:0.
http://www.gnu.org/software/libtool/manual/libtool.html#Updating-version-info
This changes the library filename (e.g. on Linux) from libsigrok.so.2.0.0
to libsigrok.so.3.0.0, the SONAME (+symlink) becomes libsigrok.so.3.
For session sources without a file descriptor to poll a negative number
should be passed for the fd parameter. The hung-chang-dso-2100 driver
currently passes 0 instead, which is the stdin stream. Fix the issue by
passing -1 for the fd parameter.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>