According to USBTMC usb488 subclass spec, wValue hast to be 0 for both
LOCAL_LOCKOUT and GO_TO_LOCAL. At least required for R&S HMO1002, the
bad request results in a STALL. Fixes bug #783.
After acquisition start, DSLogic stores samples in memory, and when done it
sends a USB packet with the trigger position.
This initial fillup can take some time. If the user requests a session stop
in between, the USB transfer is cancelled and the session hangs because it
is not closed properly.
This commit manages this case and closes the session properly when
acquisition is stopped by the user.
Signed-off-by: Diego F. Asanza <f.asanza@gmail.com>
According to the infos I have, VCD files should be plain ASCII, but we
got report of a version adding a UTF8 BOM at the beginning of the file,
so we need to skip it.
This fixes bug #755.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
For some reason, uploading the FPGA binary into DSLogic in small chunks
does not work. In this commit, the whole binary image is loaded into memory
and transfer is done in one chunk.
Furthermore, the FPGA configuration structure was not initialized
properly. This was changed with the initialization values taken from the
original DSLogic software.
Signed-off-by: Diego Asanza <f.asanza@gmail.com>
Certain output modules do not understand double-precision data.
Although we need double precision to represent the full resolution
of 7.5 digit readings, temporarily convert data to single precision
so that the output modules understand it. While the reasing might be
off by a few counts, we ensure the output modules do not display
completely bogus data.
For details, see bug #779.
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.