Implement the configuration setting TRIGGER_SOURCE with the
choices CH (logic channels) and TRG (external trigger input).
Also implement the TRIGGER_SLOPE setting for selecting the
edge to trigger on (rising or falling).
Move pre-acquisition hardware setup to the new config_commit()
callback. At the moment, the only setting applied at commit
time is switching the clock source, which involves uploading
a new bitstream to the FPGA.
Move setup of channels and trigger masks to the new probe
configuration callback. Although the actual hardware setup
still happens just before acquisition, the new approach
already has the advantage that invalid settings are caught
early.
Also, it turns out that the LWLA1034 allows triggering on
channels which are not enabled for data acquisition. This
feature is now supported as well.
Apparently, frontends may call scan() more than once to accumulate
multiple devices, so do not reset the instance list pointer at the
start of each scan. Also, number devices continuously across scans.
Report settings at acquisition start as informational messages.
Print a message when the the trigger condition has been met.
Demote some other messages from information to debug, and use
the %zu format for printing size_t values.
Allow the acquisition to be constrained by time in addition to
a sample count limit. Since the LWLA protocol actually provides
only a duration natively, implement the sample count limit on top
of the new duration limit.
With this change, limiting an acquisition in external clock mode
should finally work properly.
The g_ascii_formatd() function expects the "format" argument to start
with a '%' character, e.g. it should be "%f" or such (this is not
clearly documented in the glib API docs, but visible from the source code).
The usage of "CH%f" for example will trigger an assertion and thus make the
LWLA device unusable in practice (e.g. in PulseView on Windows no probenames
would be shown, and sampling wouldn't work).
Example:
GLib-CRITICAL **: g_ascii_formatd: assertion 'format[0] == '%'' failed
(not exposed in all glib versions or builds of glib on all distros
apparently, some may need G_MESSAGES_DEBUG=all or other measures)
From the glib g_ascii_formatd() code:
g_return_val_if_fail (format[0] == '%', NULL);
We now use g_snprintf() instead for simplicity. This has been tested to
fix this specific issue (i.e. the probenames now do show up in PulseView).
This closes bug #270.
Daniel Elstner
Uwe Hermann