From 5bc94d60a17039dfd5d46caaa292d3667fa87fb3 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Tue, 1 Apr 2014 21:35:31 +0300
Subject: [PATCH] Use current monitoring to detect failed turnouts

The turnout solenoid takes quite a bit of current, which is easy to
detect.  If there's no current spike after activating a solenoid, it
may have a broken microswitch that prevents operation.
---
 source/libr2c2/arducontrol.cpp | 21 ++++++++++++++++++++-
 source/libr2c2/arducontrol.h   |  2 ++
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/source/libr2c2/arducontrol.cpp b/source/libr2c2/arducontrol.cpp
index dbe3013..fa95a69 100644
--- a/source/libr2c2/arducontrol.cpp
+++ b/source/libr2c2/arducontrol.cpp
@@ -405,6 +405,8 @@ void ArduControl::tick()
 			acc.state.set(acc.state^lowest_bit);
 			PendingCommand cmd(acc, Accessory::ACTIVATE, i);
 			command_queue.push(cmd);
+
+			monitor.reset_peak();
 		}
 		else
 			accessory_queue.pop_front();
@@ -415,8 +417,23 @@ void ArduControl::tick()
 		Time::TimeStamp t = Time::now();
 		if(t>off_timeout)
 		{
+			Accessory &acc = *active_accessory;
+
+			if(acc.kind==Accessory::TURNOUT && monitor.get_peak()<0.5f)
+			{
+				unsigned bit = 1<<active_index;
+				if(acc.uncertain&bit)
+					acc.uncertain &= ~bit;
+				else
+				{
+					signal_turnout_failed.emit(acc.address);
+					acc.state.rollback();
+					acc.target ^= bit;
+				}
+			}
+
 			off_timeout = Time::TimeStamp();
-			PendingCommand cmd(*active_accessory, Accessory::DEACTIVATE, active_index);
+			PendingCommand cmd(acc, Accessory::DEACTIVATE, active_index);
 			command_queue.push(cmd);
 		}
 	}
@@ -526,6 +543,8 @@ ArduControl::Accessory::Accessory(Kind k, unsigned a, unsigned b):
 	address(a),
 	bits(b),
 	state(0),
+	uncertain((1<<bits)-1),
+	target(0),
 	active_time(500*Time::msec)
 { }
 
diff --git a/source/libr2c2/arducontrol.h b/source/libr2c2/arducontrol.h
index 5552809..c3ca7a4 100644
--- a/source/libr2c2/arducontrol.h
+++ b/source/libr2c2/arducontrol.h
@@ -117,6 +117,7 @@ private:
 
 		bool set(T v) { if(v==pending) return false; pending = v; ++serial; return true; }
 		bool commit(unsigned short s) { if(s!=serial) return false; current = pending; return true; }
+		void rollback() { pending = current; ++serial; }
 
 		operator T() const { return current; }
 	};
@@ -173,6 +174,7 @@ private:
 		unsigned address;
 		unsigned bits;
 		ControlledVariable<unsigned> state;
+		unsigned uncertain;
 		unsigned target;
 		Msp::Time::TimeDelta active_time;
 
-- 
2.43.0