The current DS thread model has some pretty major issues. It makes it difficult to know if all data is from the same remote packet, and if the data changes while the robot loop is running. Additionally, the DS thread is used for a few other things (MotorSafety and State Tracking for EducationalRobot). This also makes sim difficult, as user code has to wait for the thread to know it has new data.
This change completely rethinks how threading works in the driver station model.
First, the DS HAL system receives a new data callback, either from Netcomm or DriverStationSim. Inside the context of this callback, all the low latency data is read and put into a cache. Doing some investigation on the robot side, this is perfectly safe to do, and also ensures a ds packet will not be parsed before we finish reading the current packet data.
After all data is read, the cache is swapped with a 2nd buffer. This buffer just stores the data, none of the HAL DS calls read from this buffer. An event is then fired, stating there is new data ready to go.
Robot code calls HAL_UpdateDSData(). This swaps the 2nd buffer with a 3rd buffer, which always contains the current data. This data will not be updated until HAL_UpdateDSData is called again. Which solves the state problem.
The high level driver station classes have. an updateData() call, which calls HAL_UpdateDSData, and then update button state variables, then data log and update the NT FMS data table (Java also caches across the JNI boundary here, but that could trivially be removed). An extra event provider is provided, allowing other threads to know when this call has been completed.
IterativeRobotBase calls DS.updateData() at the beginning of each loop, and only once per loop. This means all commands will always have the same state.
All of this means there is no longer a DS thread. Everything happens synchronously. This means Sim and testing is easier, as you can just call DriverStationSim.NotifyNewData(), and then DriverStation.UpdateData(), and you can guarantee that all the DriverStation.*** data is up to date.
As for Motor Safety and Educational Robot State Handling, those can all be handled by their own threads. The Educational Thread only needs to run under EducationalRobot, and MotorSafety will only be started if there is a motor safety object enabled.
The existing raw time has an issue where it jumps around, as in the FPGA if the frequency is not a multiple or divisor of 25 Mhz it jumps around by 1 every second. While waiting on an FPGA change, update the API to make raw output give nanoseconds rather then a scaled value. This does a longer read cycle to get the correct value, but in the future if a fast FPGA function is added this can be easily changed.
SPI Mode setting was very broken. MSB and LSB sets did not work (MSB is the only one supported)
and if LSB was set (which was the default) the ioct to set clock phase would fail. This
deprecates all the individual functions, the LSB/MSB functions, and adds an SPI mode selection
function. This is usually more understandable, and shows up in a lot more documentation
The FPGA API takes microseconds directly, instead of a scaled value. Also add a new HAL level API to trigger multiple DIOs with the same pulse at once.
The real robot has match time set to -1.0 until it's enabled, and then
counts down. Disabling the robot sets the time to -1.0.
The sim GUI has been updated to add preset buttons for auto and teleop
match times. The enable match timing checkbox has been removed as it's
no longer required.
The DS socket plugin has also been fixed to properly initialize
matchTime to -1.0 and reset it to -1.0 on disable.
More functionality was implemented at the HAL level, so expose that to the wpilib level.
This also does units changes for all the PH related functionality.
Having PCM as a singleton is a problem, as multiple things need to use it, and that gets really ugly. This changes PCM's to be a reference counted object, that can be passed around and constructed from multiple places.
In Java, this is using a map to hold a data store with a ref count, and allocating new objects any time a duplicate is requested.
In C++, this uses a trick constructor to store a PCM instance in the data store itself. This instance can then be passed to base objects using std::shared_ptr's aliasing constructor, which means constructing a solenoid from a PCM is not allocating after the 1st one.
This did require removing sendable from PCM. A compressor class was added back in to act as sendable for the PCM.
After this change is finished, the only change RobotBuilder and Team Code would require is passing a module type to solenoid constructors.
Co-authored-by: sciencewhiz <sciencewhiz@users.noreply.github.com>
In some cases, knowing roborio 2 might be useful. This also creates a higher level enum that might be usable later for the discussion on more complex runtime types.
- Twine, StringRef, Format, and NativeFormatting have been removed
- Logging now uses fmtlib style formatting
- Nearly all uses of wpi::outs/errs have been replaced with fmt::print() or
std::puts()/std::fputs() (for unformatted strings).
- A wpi/fmt/raw_ostream.h header has been added to enable
fmt::print() with wpi::raw_ostream
Use ghc::filesystem as fill on older GCC (e.g. RoboRIO).
This can be removed once all GCC platforms have upgraded to 8.1 or later.
File open functionality has been retained from LLVM but moved to "fs" namespace
and tweaked for improved consistency with std::filesystem (e.g. error_code is
passed by reference instead of returned).
Also update WPILibC's Filesystem functions to return std::string.
* Add .clang-tidy configuration.
* A separate .clang-tidy is used for hal includes to suppress modernize-use-using
(as these are C headers).
* Add NOLINT where necessary for a clean run.
* Add clang-tidy job to lint-format workflow. This workflow is now only run on PRs.
To reduce runtime, clang-tidy is only run on files changed in the PR.
Two wpilibc changes; both are unlikely to break user code:
* BuiltInAccelerometer: Make SetRange() final
* Counter: Make SetMaxPeriod() final
After these cleanups, the only file that does not run cleanly is
cscore_raw_cv.h due to it not being standalone.
This makes code easier to read and more consistent between C++ and Java.
Also update clang-format settings to always add a line break (even if no braces are used).
This is a breaking change to the WebSockets layer to align it with
recent specification documentation work.
To support this, HAL SimValue changed readonly to a direction enum.
This allows specifying bidirectional in addition to input and output.
The SimValue change is specifically designed to avoid API and ABI breakage.
This is completely transparent in C++; in Java a new callback class was added,
and the old readonly functions have been marked deprecated.
A new SimValue creation function for enums allows specifying double values
for each enum value, not just strings. This allows mapping enum values to
doubles in the WebSockets layer.
A ":" in the SimDevice name now maps it to different WebSocket types (e.g.
"Accel:Name" becomes type "Accel", device "Name"). The type is hidden
in the GUI.
Other WebSockets changes:
* Implemented match_time and game_data
* Added joystick rumble data
* Added builtin accelerometer support
* SimValue enums are mapped to string and double value on WS interface
* Added WebSockets protocol specification
* Added READMEs
Currently, Encoder.reset() must make a round trip to the sensor and back
in order for the count to be updated for the user program. As the sim layer
also resets the internal encoder count, this creates a race condition (a WS
message with a new count can be "in flight" during a reset and update the
count).
This changes the WS layer to not put reset on the wire, but instead keep an
offset count internal to the robot program. The value on the wire is not
reset, but rather all sends and receives are adjusted as necessary to the
internal robot count.
This approach is straightforward, but does result in the value on the wire
not matching the value in the user program. A future improvement will fix
this, but this change fixes the immediate race condition problem.
