Vitaliy Vorobyov [Sun, 5 May 2019 12:16:54 +0000 (15:16 +0300)]
serial-lcr: Add MASTECH MS5308
Uwe Hermann [Wed, 1 May 2019 13:33:05 +0000 (15:33 +0200)]
Fix an issue when building in directories that are symlinks.
Explicitly use SRCDIR and BUILDDIR in Doxyfile files to reference input
files. This seems to be a sufficient fix for an issue where the build
would fail when libsigrok/ was located in a directory that was a symlink.
This fixes bug #547.
Vitaliy Vorobyov [Wed, 1 May 2019 13:54:14 +0000 (15:54 +0200)]
Add MASTECH MS2115B support.
Gerd v. Egidy [Sun, 10 Feb 2019 19:14:27 +0000 (20:14 +0100)]
agilent-dmm: add basic support for Agilent/Keysight U127x
Their commands are very similar to the U123x series, they just
add some more modes and the second channel. So use the re-functions
and just extend them where necessary.
Log reading not supported yet.
Basic testing done with a U1272A.
Gerd v. Egidy [Sun, 10 Feb 2019 19:13:46 +0000 (20:13 +0100)]
agilent-dmm: fix support for Agilent/Keysight U1252A
- fix the resolution of the CONF?-response:
the resolution is given with 6 decimal places
(instead of 8) like this:
VOLT +5.
000000E+00,+1.
000000E-04
- add more measurement modes that are possible with the meter:
CONT,COND,TEMP,PULS
Gerhard Sittig [Sun, 3 Jun 2018 10:24:55 +0000 (12:24 +0200)]
serial: rename variable to reflect it's related to libserialport
Rename the rather generic 'data' struct member to 'sp_data', to better
reflect that it contains details which are specific to libserialport.
Gerhard Sittig [Sun, 19 Mar 2017 15:11:56 +0000 (16:11 +0100)]
serial: update doxygen comments (flush vs drain, in vs out params)
It's important to remain aware that the serial layer's flush and drain
semantics differs from e.g. filesystem calls. The libserialport API is
said to follow the termios example.
Extend comments in the libsigrok API, to not depend on the libserialport
layer and the availability of its documentation. This raises awareness
during maintenance of sigrok device drivers, as well as the pending
addition of alternative transports for serial communication.
Adjust the doxygen comment for the read line routine while we are here.
Add "in" and "out" attributes for routine parameters.
Gerhard Sittig [Mon, 22 Apr 2019 08:28:07 +0000 (10:28 +0200)]
libsigrok-internal.h: fix source file references in comments
The src/hardware/ subdirectory exclusively contains device drivers these
days, while common support code has moved to the src/dmm/, src/lcr/,
src/scale/, etc directories or src/ itself. Adjust comments in the
libsigrok-internal.h declaration blocks which reference source files.
Gerhard Sittig [Mon, 22 Apr 2019 08:08:32 +0000 (10:08 +0200)]
libsigrok-internal.h: nit, alpha-sort include directives
Gerhard Sittig [Mon, 2 Oct 2017 15:26:52 +0000 (16:26 +0100)]
device: rephrase sizeof() calls for reduced redundancy, use malloc0
Just allocate the memory needed to hold the very variable's size. No
need to duplicate the variable's type. Reduces redundancy and increases
robustness during maintenance.
Use g_malloc0() in sr_serial_new() to make sure all of the structure is
initialized.
Uwe Hermann [Mon, 22 Apr 2019 11:26:47 +0000 (13:26 +0200)]
Consistently use the "Sysclk" spelling everywhere.
We use this spelling (not "SysClk") in most of the rest of the code-base,
as well as in the wiki.
Uwe Hermann [Wed, 24 Apr 2019 14:11:36 +0000 (16:11 +0200)]
udev: Add Sysclk SLA50232 entry.
Uwe Hermann [Wed, 24 Apr 2019 16:23:11 +0000 (18:23 +0200)]
sysclk-sla5032: Minor asterisk placement consistency fixes.
Uwe Hermann [Wed, 24 Apr 2019 15:29:36 +0000 (17:29 +0200)]
sysclk-sla5032: Make a few functions static.
Uwe Hermann [Wed, 24 Apr 2019 15:22:05 +0000 (17:22 +0200)]
sysclk-sla5032: Merge sla5032.[ch] into protocol.[ch].
Uwe Hermann [Wed, 24 Apr 2019 14:49:12 +0000 (16:49 +0200)]
sysclk-sla5032: Shorten sla5032_start_sample() a bit.
Uwe Hermann [Mon, 22 Apr 2019 11:17:20 +0000 (13:17 +0200)]
sysclk-sla5032: Shorten a few code snippets a bit.
Uwe Hermann [Mon, 22 Apr 2019 11:12:20 +0000 (13:12 +0200)]
sysclk-sla5032: Fix compiler warnings (max vs. MAX).
src/hardware/sysclk-sla5032/protocol.c: In function ‘la_start_acquisition’:
src/hardware/sysclk-sla5032/protocol.c:244:8: warning: implicit declaration of function ‘max’ [-Wimplicit-function-declaration]
pre = max(pre, 2);
^~~
Vitaliy Vorobyov [Mon, 22 Apr 2019 10:24:47 +0000 (12:24 +0200)]
Add initial Sysclk SLA5032 driver.
Dewelde Anthony [Tue, 16 Apr 2019 15:12:33 +0000 (17:12 +0200)]
korad-kaxxxxp: Added support for TENMA 72-2535 V2.1
Uwe Hermann [Wed, 17 Apr 2019 15:42:18 +0000 (17:42 +0200)]
scpi-pps: Fix typos and minor cosmetics.
Uwe Hermann [Wed, 17 Apr 2019 15:32:26 +0000 (17:32 +0200)]
scpi-pps: Fix "aquisition" typo everywhere.
Uwe Hermann [Wed, 17 Apr 2019 15:09:17 +0000 (17:09 +0200)]
sr_session_send_meta(): Drop unneeded check.
As of right now, sr_config_new() "cannot fail" and will never return NULL.
Frank Stettner [Thu, 11 Apr 2019 11:04:22 +0000 (13:04 +0200)]
scpi-pps: Don't use SCPI_CMD_REMOTE and SCPI_CMD_LOCAL for HP 66xxB devices when in GPIB mode.
Frank Stettner [Wed, 10 Apr 2019 12:53:39 +0000 (14:53 +0200)]
scpi-pps: Add various HP power supplies:
HP 6632A, HP 6634A, HP 6611C, HP 6612C, HP 6613C and HP 6614C
Frank Stettner [Wed, 10 Apr 2019 10:10:39 +0000 (12:10 +0200)]
scpi-pps: Implement init_acquisition() and update_status() for HP 66xxA power supplies.
Frank Stettner [Wed, 10 Apr 2019 09:54:37 +0000 (11:54 +0200)]
scpi-pps: Add config keys SR_CONF_OVER_VOLTAGE_PROTECTION_ACTIVE,
SR_CONF_OVER_CURRENT_PROTECTION_ACTIVE and
SR_CONF_OVER_TEMPERATURE_PROTECTION_ACTIVE to HP 66xxA power supplies.
Frank Stettner [Wed, 10 Apr 2019 09:39:55 +0000 (11:39 +0200)]
scpi-pps: Add SR_CONF_REGULATION for HP 66xxA power supplies.
Frank Stettner [Wed, 10 Apr 2019 09:12:00 +0000 (11:12 +0200)]
scpi-pps: Seperate existing HP 66xxA and 66xxB profiles.
Frank Stettner [Wed, 10 Apr 2019 08:28:06 +0000 (10:28 +0200)]
scpi-pps: Add missing frequency channel settings for acquisition.
Frank Stettner [Tue, 9 Apr 2019 15:43:30 +0000 (17:43 +0200)]
scpi-pps: Set device and channel group feature for HP 66xxB.
Frank Stettner [Tue, 9 Apr 2019 15:41:29 +0000 (17:41 +0200)]
scpi-pps: Add configurable sr_mqflags.
Frank Stettner [Tue, 9 Apr 2019 14:57:50 +0000 (16:57 +0200)]
scpi-pps: Implement init_acquisition() and update_status() for HP 66xxB power supplies.
Frank Stettner [Thu, 11 Apr 2019 12:33:19 +0000 (14:33 +0200)]
scpi_libgpib: Add mutex to SPoll.
Frank Stettner [Thu, 11 Apr 2019 11:03:11 +0000 (13:03 +0200)]
scpi: Add enum scpi_transport_layer.
Frank Stettner [Tue, 9 Apr 2019 14:13:32 +0000 (16:13 +0200)]
scpi-pps: Add init_acquisition() and update_status() for device specific
acquisition functions.
Frank Stettner [Tue, 9 Apr 2019 13:47:19 +0000 (15:47 +0200)]
scpi-pps: Add config keys SR_CONF_OVER_VOLTAGE_PROTECTION_ACTIVE,
SR_CONF_OVER_CURRENT_PROTECTION_ACTIVE and
SR_CONF_OVER_TEMPERATURE_PROTECTION_ACTIVE to HP 66xxB power supplies.
Frank Stettner [Tue, 9 Apr 2019 13:29:30 +0000 (15:29 +0200)]
scpi-pps: Add SR_CONF_REGULATION for HP 66xxB power supplies.
Frank Stettner [Tue, 9 Apr 2019 13:27:09 +0000 (15:27 +0200)]
scpi-pps: Add enum pps_scpi_dialect and add to struct scpi_pps,
preset with reasonable values.
Frank Stettner [Tue, 9 Apr 2019 12:12:31 +0000 (14:12 +0200)]
session: Add helper sr_session_send_meta() to send SR_DF_META packages.
Replace individual functions in drivers for arachnid-labs-re-load-pro
and lcr/es51919 with sr_session_send_meta() helper function.
Uwe Hermann [Fri, 29 Mar 2019 15:23:21 +0000 (16:23 +0100)]
demo: Minor cosmetics.
Frank Stettner [Thu, 21 Mar 2019 22:04:58 +0000 (23:04 +0100)]
korad-kaxxxxp: Add another KA3005P with 0xBC as extra byte in the model ID.
Frank Stettner [Thu, 21 Mar 2019 17:43:39 +0000 (18:43 +0100)]
korad-kaxxxxp: Add SR_MQFLAG_DC flag to the current channel package.
Frank Stettner [Sat, 16 Mar 2019 22:44:38 +0000 (23:44 +0100)]
scpi: Add connenction_id() function to all scpi drivers.
Frank Stettner [Thu, 21 Feb 2019 15:47:25 +0000 (16:47 +0100)]
demo: Get/Set new config key offset.
Frank Stettner [Thu, 21 Feb 2019 15:46:36 +0000 (16:46 +0100)]
Add new config key OFFSET.
Frank Stettner [Thu, 21 Feb 2019 15:34:17 +0000 (16:34 +0100)]
demo: Get/Set amplitude while data acquisition is running.
Frank Stettner [Wed, 20 Feb 2019 19:32:04 +0000 (20:32 +0100)]
demo: Get/Set measurement quantity for the analog channels.
Frank Stettner [Wed, 20 Feb 2019 17:58:13 +0000 (18:58 +0100)]
demo: Set an initial mq, mq flag and digits to the analog package.
Without a measured quantity in packet.meaning->mq the C++ binding function
sigrok::Analog::mq() throws an exception and there is no way to check if
there is any measured quantity set in the analog package.
Frank Stettner [Tue, 19 Feb 2019 15:57:48 +0000 (16:57 +0100)]
Free sr_config and sr_config lists in meta datafeeds correctly.
Soeren Apel [Sun, 24 Mar 2019 20:33:54 +0000 (21:33 +0100)]
input/trace32_ad: Add support for new file format (BINHDR2)
Soeren Apel [Sun, 24 Mar 2019 12:48:44 +0000 (13:48 +0100)]
input/trace32_ad: Use only hex offsets
Uwe Hermann [Thu, 21 Mar 2019 23:59:39 +0000 (00:59 +0100)]
chronovu-la: Fix broken triggering.
This fixes bug #1369.
Thomas Andres [Sun, 17 Mar 2019 16:06:28 +0000 (17:06 +0100)]
korad-kaxxxxp: support for Stamos S-LS-31 power supply
Michael Klengel [Wed, 13 Feb 2019 09:50:19 +0000 (10:50 +0100)]
manson-hcs-3xxx: Add HCS-3300 / DPPS-32-15 / HCS-3302 support.
Manson HCS-3300 (1-16 V, 30 A):
$ sigrok-cli --show -d manson-hcs-3xxx:conn=/dev/cu.SLAB_USBtoUART5
[...]
sr: manson-hcs-3xxx: Unknown model ID 'HCS-3300' detected, aborting.
Voltcraft DPPS-32-15 (1-32 V, 15 A), identical to Manson HCS-3302:
$ sigrok-cli --show -d manson-hcs-3xxx:conn=/dev/cu.SLAB_USBtoUART
[...]
sr: manson-hcs-3xxx: Unknown model ID 'HCS-3302' detected, aborting.
Michael Klengel [Wed, 13 Feb 2019 09:50:18 +0000 (10:50 +0100)]
manson-hcs-3xxx: Whitespace changes for models[].
Frank Stettner [Fri, 1 Feb 2019 11:18:46 +0000 (12:18 +0100)]
hp-3478a: Check via GPIB serial poll if new data is available.
When just reading the data without check, the bus is blocked until new
data is available.
Uwe Hermann [Tue, 29 Jan 2019 22:15:37 +0000 (23:15 +0100)]
ipdbg-la: Minor cosmetic and comment fixes.
Daniel Anselmi [Fri, 18 Jan 2019 02:03:02 +0000 (03:03 +0100)]
ipdbg-la: improve speed
danselmi [Thu, 17 Jan 2019 11:31:23 +0000 (12:31 +0100)]
ipdbg-la: working on windows
Wolfram Sang [Wed, 2 Jan 2019 12:15:25 +0000 (13:15 +0100)]
ols: add feature to support >256K memory
Add support for the Pepino-style of accessing >256K of memory. Because
this the only known extension of accessing >256K currently, we apply it
as soon as the sample size is bigger than 256K. Let's hope other
devices (if any) will follow this style. If not, we need to add support
depending on the device name later.
Signed-off-by: Wolfram Sang <redacted>
Wolfram Sang [Wed, 2 Jan 2019 12:15:24 +0000 (13:15 +0100)]
pipistrello: rename registers to match actual function
Magnus (creator of the Pipistrello) confirmed that he mixed up the
register names. The code was doing it correctly nonetheless but was
confusing to read because of this. Fix it to make it easier to
comprehend.
Signed-off-by: Wolfram Sang <redacted>
Wolfram Sang [Wed, 2 Jan 2019 12:15:23 +0000 (13:15 +0100)]
ols: mention compatible devices in driver name
Signed-off-by: Wolfram Sang <redacted>
Wolfram Sang [Wed, 2 Jan 2019 12:15:22 +0000 (13:15 +0100)]
ols: extend reponse delay when scanning device
My Pepino needs 15ms instead of 10ms, so let's use 20ms to be on the
safe side.
Signed-off-by: Wolfram Sang <redacted>
Wolfram Sang [Wed, 2 Jan 2019 12:15:21 +0000 (13:15 +0100)]
ols: sort commands according to their hex value
Makes adding new ones easier.
Signed-off-by: Wolfram Sang <redacted>
Wolfram Sang [Wed, 2 Jan 2019 12:15:20 +0000 (13:15 +0100)]
ols: refactor using max_channels
Let max_channels really carry the number of maximum channels the
hardware supports. We will handle the limitation of only half the
channels available in 200MHz mode later. Note that there won't be a
regression because we only set the variable but never check it. The
desired result of this patch is the removal of the NUM_CHANNELS macro.
The number of channels needs to be dealt with at runtime.
Signed-off-by: Wolfram Sang <redacted>
Wolfram Sang [Wed, 2 Jan 2019 12:15:19 +0000 (13:15 +0100)]
ols: refactor channel initialization
We needs this twice so put it into a seperate function, so updates to it
will automatically handled for both callers.
Signed-off-by: Wolfram Sang <redacted>
Wolfram Sang [Wed, 2 Jan 2019 12:15:18 +0000 (13:15 +0100)]
ols: simplify calculation of readcount
Somewhen we probably want DIV_ROUND_UP from the Kernel.
Signed-off-by: Wolfram Sang <redacted>
Wolfram Sang [Wed, 2 Jan 2019 12:15:17 +0000 (13:15 +0100)]
ols: drop wrong usage of macro
commit
f51acd69 ("ols: combine demux samples") wrongly replaced the bit
pattern of 0x20 with the number of channels which just happens to be 32
as well. So, the code works but is confusing to read. Reword the
for-loop to make it more comprehensible.
Signed-off-by: Wolfram Sang <redacted>
Wolfram Sang [Wed, 2 Jan 2019 12:15:16 +0000 (13:15 +0100)]
ols: use 32bit for handling sample counts
The OLS protocol sends 16bit values to specify the sample count and
delay count. However, this 16bit value is the number of 32bit words to
be sampled, so the actual sample count is 4 times larger and does not
fit into a uint16_t. Extend it to support the full range of 256K
(LogicShrimp will need this) and to prepare support for devices with
even more memory (Pepino).
Signed-off-by: Wolfram Sang <redacted>
Wolfram Sang [Wed, 2 Jan 2019 12:15:15 +0000 (13:15 +0100)]
ols: remove needless initialization
channel_mask is recalculated before it gets accessed, so this
initialization is not needed.
Signed-off-by: Wolfram Sang <redacted>
Wolfram Sang [Wed, 2 Jan 2019 12:15:14 +0000 (13:15 +0100)]
ols: remove unused define
Signed-off-by: Wolfram Sang <redacted>
Gerhard Sittig [Thu, 5 Oct 2017 23:38:26 +0000 (01:38 +0200)]
uni-t-ut32x: rephrase the receive buffer and packets relation
The previous implementation assumed that a receive data chunk ends
exactly with a sensor packet's end. Yet the buffer had 32 bytes while
the packets have 19 bytes.
Separate the data reception from the packet processing. Collect whatever
chunks the USB connection provides, and scan the resulting buffer for
packets. Cope with either incomplete or corrupt or misaligned packets as
well as with multiple packets in receive chunks. The latter might happen
upon initial synchronization, when a device already sends data or the
serial port buffered previously communicated data.
In the regular case, the computer will process so fast that each single
character will be handled individually. We don't mind. The frequency is
some 60 times per second, and the data volume is 19 bytes. The software
works for the regular case, and synchronizes fast at startup or after
comm errors.
Gerhard Sittig [Thu, 5 Oct 2017 22:34:05 +0000 (00:34 +0200)]
uni-t-ut32x: improve robustness of packet parser, more diagnostics
Always print the data bytes of received buffers in the packet parser,
then check some more fixed fields to not process invalid packets, then
process the packet content as the previous implementation did.
Call the packet parser for incomplete packets and discarded input
buffers as well (initial synchronization, re-sync after comm errors).
This results in the availability of more diagnostics during development.
Pass the packet's location and size from outside. This prepares the
logic to cope with situations where the receive buffer contains multiple
(potentially incomplete) packets.
Gerhard Sittig [Thu, 5 Oct 2017 22:09:44 +0000 (00:09 +0200)]
uni-t-ut32x: use ASCII literals in packet parser, symbols for magic numbers
Slightly unobfuscate the UT32x packet parser. The protocol is mostly
ASCII based, checks for hex numbers may be unexpected. Use symbolic
identifiers for the packet length and some special characters.
Gerhard Sittig [Thu, 5 Oct 2017 21:26:38 +0000 (23:26 +0200)]
uni-t-ut32x: comment on the "T1-T2" channel name (looks like a range)
Gerhard Sittig [Thu, 5 Oct 2017 21:16:50 +0000 (23:16 +0200)]
uni-t-ut32x: use common code for sw limits, minor data type fixup (data source)
Gerhard Sittig [Thu, 5 Oct 2017 09:35:25 +0000 (11:35 +0200)]
uni-t-ut32x: pre-set to default conn= spec
The previous implementation of the UT32x driver expected to see a conn=
spec, without it no device is found. Default to the USB identification
of the CH9325 chip, to make the driver work out of the box. Users still
can provide conn= specs and override the default for other cables.
Gerhard Sittig [Sun, 30 Dec 2018 11:31:20 +0000 (12:31 +0100)]
doc: update README.devices (USB detection, enable serial comm)
Slightly rephrase README.devices since there is no strict distinction
into "fully automatic" and "always manual". Some drivers _accept_ conn=
specs when provided, _and_ support automatic detection of enumerable
devices, _and_ might implement defaults but also support overrides.
Nit, numerically sort the list of Uni-T cables (which is about to grow
in the future) for improved readability.
Add two more devices which require users to manually enable the serial
communication (Brymen BM257s, EEVBlog 121GW).
Martin Ling [Sun, 30 Dec 2018 03:01:21 +0000 (04:01 +0100)]
bindings: Add Output::format()
Martin Ling [Sat, 29 Dec 2018 02:18:05 +0000 (03:18 +0100)]
rigol-ds: Fix memory buffer readout on DS4000 series.
majekw [Sun, 2 Dec 2018 12:49:44 +0000 (13:49 +0100)]
Add support for YiXingDianZi MDSO in hantek-6xxx driver.
Mike Williams [Wed, 5 Dec 2018 19:46:26 +0000 (14:46 -0500)]
scpi-pps: add support for BK Precision 9130
Mike Williams [Wed, 5 Dec 2018 17:47:52 +0000 (12:47 -0500)]
scpi-dmm: add experimental Keysight 34465A support
Tested DC current, DC voltage, and resistance. Instrument gives an error
only on first measurement but the output of the measurements is correct.
Uwe Hermann [Fri, 28 Dec 2018 12:01:45 +0000 (13:01 +0100)]
contrib/60-libsigrok.rules: Mention FT232H/ftdi-la item.
Paul [Wed, 19 Dec 2018 20:23:57 +0000 (21:23 +0100)]
ftdi-la: added FT232H device ID
Martin Ling [Thu, 27 Dec 2018 19:38:30 +0000 (20:38 +0100)]
bindings: Add new Context::create_end_packet() method.
Martin Ling [Thu, 27 Dec 2018 19:38:06 +0000 (20:38 +0100)]
python: Add override for Context.create_logic_packet()
Gerhard Sittig [Thu, 20 Dec 2018 18:10:27 +0000 (19:10 +0100)]
dmm/eev121gw: fix a typo in a comment
Gerhard Sittig [Wed, 19 Dec 2018 11:41:29 +0000 (12:41 +0100)]
pickit2: avoid NULL dereference in close code path
Daniel Anselmi [Tue, 4 Dec 2018 00:55:00 +0000 (01:55 +0100)]
ipdbg-la: Check if limit samples is valid (leq size of ringuffer)
Martin Ling [Thu, 20 Sep 2018 20:12:28 +0000 (21:12 +0100)]
Don't reference SR_PACKAGE_VERSION_STRING directly in backend.c.
Reporting build versus runtime versions makes sense for a client,
but not inside the library itself.
Martin Ling [Thu, 20 Sep 2018 19:42:11 +0000 (20:42 +0100)]
Don't reference SR_PACKAGE_VERSION_STRING directly in output modules.
Uwe Hermann [Thu, 20 Dec 2018 07:52:51 +0000 (08:52 +0100)]
drivers: Make per-driver sr_dev_driver structs static.
Uwe Hermann [Thu, 20 Dec 2018 07:35:06 +0000 (08:35 +0100)]
microchip-pickit2: Drop unneeded prefix.
Uwe Hermann [Thu, 20 Dec 2018 07:32:56 +0000 (08:32 +0100)]
microchip-pickit2: Minor cosmetics.
Gerhard Sittig [Tue, 11 Dec 2018 14:14:13 +0000 (15:14 +0100)]
microchip-pickit2: first driver implementation (acquisition works, triggers don't)
Fill in the scan, open/close, get/set/list, acquisition start/stop logic
such that data acquisition with a PICkit2 works.
Trigger support needs more attention. User specified triggers either
seem to not take effect, or the trigger position is not in the expected
location. It's yet to get determined what's the issue.
This implementation is based on protocol information gathered from the
pk2-la project.
Gerhard Sittig [Tue, 11 Dec 2018 11:18:07 +0000 (12:18 +0100)]
microchip-pickit2: Initial driver skeleton.
Gerhard Sittig [Tue, 11 Dec 2018 15:52:06 +0000 (16:52 +0100)]
brymen-bm86x: drop redundant free call, fixup channel index
Remove a free() call in an error path for a list which immediately
before the call was determined to be NULL. Use index 0 and 1 for
channels P1 and P2 respectively (the previous implementation used 0
for both channels).
Gerhard Sittig [Sat, 17 Nov 2018 18:51:31 +0000 (19:51 +0100)]
scpi-dmm: run OPC queries immediately before essential commands
The current implementation of the SCPI DMM driver is conservative about
checking the device's being operational, but the *OPC? queries are found
in unfortunate locations. Run the OPC query right before running the
next "actual" command, not afterwards. And certainly not between sending
requests and potentially gathering responses in subsequent calls.
This commit does not change current behaviour, but improves maintenance
before pending commits.