Move y2012 over to new SensorReader class

While we are here, shove the RobotState sender and DMA tick code into
the base class.

Change-Id: I49e6b3902c1ee46d396ccc77c2b8dce825e891d8
diff --git a/frc971/wpilib/BUILD b/frc971/wpilib/BUILD
index d0f6bce..27f9190 100644
--- a/frc971/wpilib/BUILD
+++ b/frc971/wpilib/BUILD
@@ -21,9 +21,9 @@
     deps = [
         ":dma",
         ":dma_edge_counting",
-        "//aos/mutex:mutex",
-        "//aos/logging",
         "//aos:init",
+        "//aos/logging",
+        "//aos/mutex",
         "//third_party:wpilib",
     ],
 )
@@ -54,10 +54,10 @@
     ],
     restricted_to = ["//tools:roborio"],
     deps = [
-        "//aos/stl_mutex:stl_mutex",
-        "//aos/time:time",
-        "//aos/logging",
         "//aos:init",
+        "//aos/logging",
+        "//aos/stl_mutex",
+        "//aos/time",
         "//third_party:wpilib",
     ],
 )
@@ -89,8 +89,8 @@
     ],
     restricted_to = ["//tools:roborio"],
     deps = [
-        "//aos/time:time",
         "//aos/logging",
+        "//aos/time",
         "//third_party:wpilib",
     ],
 )
@@ -106,12 +106,12 @@
     restricted_to = ["//tools:roborio"],
     deps = [
         ":gyro_interface",
-        "//aos/time:time",
+        "//aos:init",
         "//aos/logging",
         "//aos/logging:queue_logging",
-        "//aos/robot_state:robot_state",
+        "//aos/robot_state",
+        "//aos/time",
         "//aos/util:phased_loop",
-        "//aos:init",
         "//frc971/queues:gyro",
         "//frc971/zeroing:averager",
     ],
@@ -127,8 +127,8 @@
     ],
     restricted_to = ["//tools:roborio"],
     deps = [
-        "//aos/mutex:mutex",
-        "//aos/time:time",
+        "//aos/mutex",
+        "//aos/time",
         "//frc971/queues:gyro",
         "//third_party:wpilib",
     ],
@@ -143,11 +143,11 @@
         "loop_output_handler.h",
     ],
     deps = [
-        "//aos/scoped:scoped_fd",
-        "//aos/time:time",
-        "//aos/robot_state:robot_state",
-        "//aos/util:log_interval",
         "//aos:init",
+        "//aos/robot_state",
+        "//aos/scoped:scoped_fd",
+        "//aos/time",
+        "//aos/util:log_interval",
     ],
 )
 
@@ -161,10 +161,10 @@
     ],
     restricted_to = ["//tools:roborio"],
     deps = [
-        "//aos/logging:queue_logging",
-        "//aos/robot_state:robot_state",
-        "//aos/network:team_number",
         "//aos:init",
+        "//aos/logging:queue_logging",
+        "//aos/network:team_number",
+        "//aos/robot_state",
         "//third_party:wpilib",
     ],
 )
@@ -180,7 +180,7 @@
     restricted_to = ["//tools:roborio"],
     deps = [
         "//aos/logging:queue_logging",
-        "//aos/robot_state:robot_state",
+        "//aos/robot_state",
         "//third_party:wpilib",
     ],
 )
@@ -203,9 +203,9 @@
     restricted_to = ["//tools:roborio"],
     deps = [
         ":pdp_values",
+        "//aos:init",
         "//aos/logging:queue_logging",
         "//aos/util:phased_loop",
-        "//aos:init",
         "//third_party:wpilib",
     ],
 )
@@ -240,11 +240,11 @@
     deps = [
         ":imu_queue",
         ":spi_rx_clearer",
-        "//aos/time:time",
+        "//aos:init",
         "//aos/logging",
         "//aos/logging:queue_logging",
-        "//aos/robot_state:robot_state",
-        "//aos:init",
+        "//aos/robot_state",
+        "//aos/time",
         "//frc971/zeroing:averager",
         "//third_party:wpilib",
     ],
@@ -283,16 +283,17 @@
         "sensor_reader.cc",
     ],
     hdrs = [
-        "sensor_reader.h"
+        "sensor_reader.h",
     ],
     restricted_to = ["//tools:roborio"],
     deps = [
-        "//aos/stl_mutex",
-        "//aos/time:time",
-        "//aos/util:phased_loop",
-        "//aos:init",
-        "//third_party:wpilib",
         ":dma",
         ":dma_edge_counting",
+        ":wpilib_interface",
+        "//aos:init",
+        "//aos/stl_mutex",
+        "//aos/time",
+        "//aos/util:phased_loop",
+        "//third_party:wpilib",
     ],
 )
diff --git a/frc971/wpilib/sensor_reader.cc b/frc971/wpilib/sensor_reader.cc
index 2f50c4a..6ce1995 100644
--- a/frc971/wpilib/sensor_reader.cc
+++ b/frc971/wpilib/sensor_reader.cc
@@ -8,26 +8,44 @@
 #include "aos/util/phased_loop.h"
 #include "frc971/wpilib/ahal/DigitalInput.h"
 #include "frc971/wpilib/ahal/Utility.h"
+#include "frc971/wpilib/wpilib_interface.h"
 
 namespace frc971 {
 namespace wpilib {
 
-SensorReader::SensorReader() {}
+SensorReader::SensorReader() {
+  // Set some defaults.  We don't tend to exceed these, so old robots should
+  // just work with them.
+  UpdateFastEncoderFilterHz(500000);
+  UpdateMediumEncoderFilterHz(100000);
+}
+
+void SensorReader::UpdateFastEncoderFilterHz(int hz) {
+  fast_encoder_filter_.SetPeriodHz(::std::max(hz, 100000));
+}
+
+void SensorReader::UpdateMediumEncoderFilterHz(int hz) {
+  medium_encoder_filter_.SetPeriodHz(::std::max(hz, 50000));
+}
 
 void SensorReader::set_drivetrain_left_encoder(
     ::std::unique_ptr<frc::Encoder> encoder) {
   fast_encoder_filter_.Add(encoder.get());
   drivetrain_left_encoder_ = ::std::move(encoder);
+  drivetrain_left_encoder_->SetMaxPeriod(0.005);
 }
 
 void SensorReader::set_drivetrain_right_encoder(
     ::std::unique_ptr<frc::Encoder> encoder) {
   fast_encoder_filter_.Add(encoder.get());
   drivetrain_right_encoder_ = ::std::move(encoder);
+  drivetrain_right_encoder_->SetMaxPeriod(0.005);
 }
 
 // All of the DMA-related set_* calls must be made before this, and it
 // doesn't hurt to do all of them.
+// TODO(austin): Does anyone actually do anything other than set this?  Or can
+// we just take care of that automatically?
 void SensorReader::set_dma(::std::unique_ptr<DMA> dma) {
   dma_synchronizer_.reset(
       new ::frc971::wpilib::DMASynchronizer(::std::move(dma)));
@@ -109,16 +127,25 @@
 void SensorReader::operator()() {
   ::aos::SetCurrentThreadName("SensorReader");
 
-  my_pid_ = getpid();
+  int32_t my_pid = getpid();
 
   dma_synchronizer_->Start();
+  if (pwm_trigger_) {
+    last_period_ = chrono::microseconds(5050);
+    LOG(INFO, "Using PWM trigger and a 5.05 ms period\n");
+  } else {
+    LOG(INFO, "Defaulting to open loop pwm synchronization\n");
+    last_period_ = chrono::microseconds(5000);
+  }
+  ::aos::time::PhasedLoop phased_loop(
+      last_period_,
+      pwm_trigger_ ? ::std::chrono::milliseconds(3) : chrono::milliseconds(4));
 
-  ::aos::time::PhasedLoop phased_loop(last_period_,
-                                      ::std::chrono::milliseconds(3));
-  chrono::nanoseconds filtered_period = last_period_;
-
-  ::std::thread pwm_detecter_thread(
-      ::std::bind(&SensorReader::RunPWMDetecter, this));
+  ::std::thread pwm_detecter_thread;
+  if (pwm_trigger_) {
+    pwm_detecter_thread =
+        ::std::thread(::std::bind(&SensorReader::RunPWMDetecter, this));
+  }
 
   ::aos::SetCurrentThreadRealtimePriority(40);
   while (run_) {
@@ -128,28 +155,35 @@
         LOG(WARNING, "SensorReader skipped %d iterations\n", iterations - 1);
       }
     }
+
+    ::frc971::wpilib::SendRobotState(my_pid);
     RunIteration();
+    dma_synchronizer_->RunIteration();
 
-    monotonic_clock::time_point last_tick_timepoint;
-    chrono::nanoseconds period;
-    {
-      ::std::unique_lock<::aos::stl_mutex> locker(tick_time_mutex_);
-      last_tick_timepoint = last_tick_time_monotonic_timepoint_;
-      period = last_period_;
+    if (pwm_trigger_) {
+      monotonic_clock::time_point last_tick_timepoint;
+      chrono::nanoseconds period;
+      {
+        ::std::unique_lock<::aos::stl_mutex> locker(tick_time_mutex_);
+        last_tick_timepoint = last_tick_time_monotonic_timepoint_;
+        period = last_period_;
+      }
+
+      if (last_tick_timepoint == monotonic_clock::min_time) {
+        continue;
+      }
+      chrono::nanoseconds new_offset = phased_loop.OffsetFromIntervalAndTime(
+          period, last_tick_timepoint + chrono::microseconds(2050));
+
+      // TODO(austin): If this is the first edge in a while, skip to it (plus
+      // an offset). Otherwise, slowly drift time to line up.
+
+      phased_loop.set_interval_and_offset(period, new_offset);
     }
-
-    if (last_tick_timepoint == monotonic_clock::min_time) {
-      continue;
-    }
-    chrono::nanoseconds new_offset = phased_loop.OffsetFromIntervalAndTime(
-        period, last_tick_timepoint + chrono::microseconds(2050));
-
-    // TODO(austin): If this is the first edge in a while, skip to it (plus
-    // an offset). Otherwise, slowly drift time to line up.
-
-    phased_loop.set_interval_and_offset(period, new_offset);
   }
-  pwm_detecter_thread.join();
+  if (pwm_trigger_) {
+    pwm_detecter_thread.join();
+  }
 }
 
 }  // namespace wpilib
diff --git a/frc971/wpilib/sensor_reader.h b/frc971/wpilib/sensor_reader.h
index b3ced4c..0ce203c 100644
--- a/frc971/wpilib/sensor_reader.h
+++ b/frc971/wpilib/sensor_reader.h
@@ -21,6 +21,10 @@
  public:
   SensorReader();
 
+  // Updates the fast and medium encoder filter frequencies.
+  void UpdateFastEncoderFilterHz(int hz);
+  void UpdateMediumEncoderFilterHz(int hz);
+
   // Sets the left drivetrain encoder.
   void set_drivetrain_left_encoder(::std::unique_ptr<frc::Encoder> encoder);
 
@@ -41,29 +45,27 @@
   void operator()();
 
  protected:
+  frc::DigitalGlitchFilter fast_encoder_filter_, medium_encoder_filter_;
+
+  ::std::unique_ptr<frc::Encoder> drivetrain_left_encoder_,
+      drivetrain_right_encoder_;
+
+ private:
   // Uses the pwm trigger to find the pwm cycle width and offset for that
   // iteration.
   void RunPWMDetecter();
 
-  int32_t my_pid_;
-
   ::std::unique_ptr<frc::DigitalInput> pwm_trigger_;
 
-  frc::DigitalGlitchFilter fast_encoder_filter_, medium_encoder_filter_,
-      hall_filter_;
-
   // Mutex to manage access to the period and tick time variables.
   ::aos::stl_mutex tick_time_mutex_;
   monotonic_clock::time_point last_tick_time_monotonic_timepoint_ =
       monotonic_clock::min_time;
-  chrono::nanoseconds last_period_ = chrono::microseconds(5050);
+  chrono::nanoseconds last_period_;
 
   ::std::unique_ptr<::frc971::wpilib::DMASynchronizer> dma_synchronizer_;
 
   ::std::atomic<bool> run_{true};
-
-  ::std::unique_ptr<frc::Encoder> drivetrain_left_encoder_,
-      drivetrain_right_encoder_;
 };
 
 }  // namespace wpilib
diff --git a/y2012/BUILD b/y2012/BUILD
index 5e85c3d..159632b 100644
--- a/y2012/BUILD
+++ b/y2012/BUILD
@@ -57,6 +57,7 @@
         "//frc971/wpilib:joystick_sender",
         "//frc971/wpilib:logging_queue",
         "//frc971/wpilib:loop_output_handler",
+        "//frc971/wpilib:sensor_reader",
         "//frc971/wpilib:wpilib_interface",
         "//frc971/wpilib:wpilib_robot_base",
         "//third_party:wpilib",
diff --git a/y2012/wpilib_interface.cc b/y2012/wpilib_interface.cc
index b5be8f4..27e8b77 100644
--- a/y2012/wpilib_interface.cc
+++ b/y2012/wpilib_interface.cc
@@ -29,7 +29,6 @@
 #include "aos/util/log_interval.h"
 #include "aos/util/phased_loop.h"
 #include "aos/util/wrapping_counter.h"
-
 #include "frc971/control_loops/drivetrain/drivetrain.q.h"
 #include "frc971/wpilib/buffered_pcm.h"
 #include "frc971/wpilib/buffered_solenoid.h"
@@ -41,7 +40,7 @@
 #include "frc971/wpilib/joystick_sender.h"
 #include "frc971/wpilib/logging.q.h"
 #include "frc971/wpilib/loop_output_handler.h"
-#include "frc971/wpilib/wpilib_interface.h"
+#include "frc971/wpilib/sensor_reader.h"
 #include "y2012/control_loops/accessories/accessories.q.h"
 
 #ifndef M_PI
@@ -69,43 +68,11 @@
          (3.5 /*wheel diameter*/ * 2.54 / 100.0 * M_PI) * 2.0 / 2.0;
 }
 
-class SensorReader {
+class SensorReader : public ::frc971::wpilib::SensorReader {
  public:
   SensorReader() {}
 
-  void set_drivetrain_left_encoder(::std::unique_ptr<Encoder> encoder) {
-    drivetrain_left_encoder_ = ::std::move(encoder);
-    drivetrain_left_encoder_->SetMaxPeriod(0.005);
-  }
-
-  void set_drivetrain_right_encoder(::std::unique_ptr<Encoder> encoder) {
-    drivetrain_right_encoder_ = ::std::move(encoder);
-    drivetrain_right_encoder_->SetMaxPeriod(0.005);
-  }
-
-  void operator()() {
-    ::aos::SetCurrentThreadName("SensorReader");
-
-    my_pid_ = getpid();
-
-    ::aos::time::PhasedLoop phased_loop(::std::chrono::milliseconds(5),
-                                        ::std::chrono::milliseconds(4));
-
-    ::aos::SetCurrentThreadRealtimePriority(40);
-    while (run_) {
-      {
-        const int iterations = phased_loop.SleepUntilNext();
-        if (iterations != 1) {
-          LOG(WARNING, "SensorReader skipped %d iterations\n", iterations - 1);
-        }
-      }
-      RunIteration();
-    }
-  }
-
   void RunIteration() {
-    ::frc971::wpilib::SendRobotState(my_pid_);
-
     {
       auto drivetrain_message = drivetrain_queue.position.MakeMessage();
       drivetrain_message->right_encoder =
@@ -122,15 +89,6 @@
 
     accessories_queue.position.MakeMessage().Send();
   }
-
-  void Quit() { run_ = false; }
-
- private:
-  int32_t my_pid_;
-
-  ::std::unique_ptr<Encoder> drivetrain_left_encoder_;
-  ::std::unique_ptr<Encoder> drivetrain_right_encoder_;
-  ::std::atomic<bool> run_{true};
 };
 
 class SolenoidWriter {
@@ -301,6 +259,7 @@
     ::std::thread joystick_thread(::std::ref(joystick_sender));
 
     SensorReader reader;
+    reader.set_dma(make_unique<DMA>());
 
     reader.set_drivetrain_left_encoder(make_encoder(0));
     reader.set_drivetrain_right_encoder(make_encoder(1));
diff --git a/y2018/wpilib_interface.cc b/y2018/wpilib_interface.cc
index dea6a7b..6ddcd41 100644
--- a/y2018/wpilib_interface.cc
+++ b/y2018/wpilib_interface.cc
@@ -380,7 +380,6 @@
 
     ::aos::time::PhasedLoop phased_loop(last_period_,
                                         ::std::chrono::milliseconds(3));
-    chrono::nanoseconds filtered_period = last_period_;
 
     ::std::thread pwm_detecter_thread(
         ::std::bind(&SensorReader::RunPWMDetecter, this));
diff --git a/y2019/wpilib_interface.cc b/y2019/wpilib_interface.cc
index ff5839f..7a6a360 100644
--- a/y2019/wpilib_interface.cc
+++ b/y2019/wpilib_interface.cc
@@ -38,7 +38,6 @@
 #include "frc971/wpilib/loop_output_handler.h"
 #include "frc971/wpilib/pdp_fetcher.h"
 #include "frc971/wpilib/sensor_reader.h"
-#include "frc971/wpilib/wpilib_interface.h"
 #include "frc971/wpilib/wpilib_robot_base.h"
 #include "y2019/constants.h"
 
@@ -107,20 +106,11 @@
   SensorReader() {
     // Set to filter out anything shorter than 1/4 of the minimum pulse width
     // we should ever see.
-    fast_encoder_filter_.SetPeriodNanoSeconds(
-        static_cast<int>(1 / 4.0 /* built-in tolerance */ /
-                             kMaxFastEncoderPulsesPerSecond * 1e9 +
-                         0.5));
-    medium_encoder_filter_.SetPeriodNanoSeconds(
-        static_cast<int>(1 / 4.0 /* built-in tolerance */ /
-                             kMaxMediumEncoderPulsesPerSecond * 1e9 +
-                         0.5));
-    hall_filter_.SetPeriodNanoSeconds(100000);
+    UpdateFastEncoderFilterHz(kMaxFastEncoderPulsesPerSecond);
+    UpdateMediumEncoderFilterHz(kMaxMediumEncoderPulsesPerSecond);
   }
 
   void RunIteration() override {
-    ::frc971::wpilib::SendRobotState(my_pid_);
-
     {
       auto drivetrain_message = drivetrain_queue.position.MakeMessage();
       drivetrain_message->left_encoder =
@@ -135,8 +125,6 @@
 
       drivetrain_message.Send();
     }
-
-    dma_synchronizer_->RunIteration();
   }
 };