commit 3dfaafdacaeaf2b21ff24f3cb314b71c911e2cea
author James Feist <james.feist@linux.intel.com> Thu Sep 20 15:46:58 2018 -0700
committer James Feist <james.feist@linux.intel.com> Fri Sep 21 12:13:58 2018 -0700
tree 80ae538890b851786c8d46898b905b1af12735cf
parent 9f044415a21272b554fa7594ade21927154afcb0

Add hysteresis to stepwise controller

Tested-by: Ran on platform monitoring output and wrote
unit test

Change-Id: I74a1d21544c1a9cb4c1cb26dd4a353cbff0442d0
Signed-off-by: James Feist <james.feist@linux.intel.com>

pid/ec/stepwise.cpp

diff --git a/pid/ec/stepwise.cpp b/pid/ec/stepwise.cpp
index 4246fb3..4a71532 100644
--- a/pid/ec/stepwise.cpp
+++ b/pid/ec/stepwise.cpp
@@ -16,6 +16,7 @@
 
 #include "stepwise.hpp"
 
+#include <cmath>
 #include <cstddef>
 #include <limits>
 
@@ -29,7 +30,7 @@
     for (size_t ii = 1; ii < ec::maxStepwisePoints; ii++)
     {
 
-        if (info.reading[ii] == std::numeric_limits<float>::quiet_NaN())
+        if (std::isnan(info.reading[ii]))
         {
             break;
         }

pid/ec/stepwise.hpp

diff --git a/pid/ec/stepwise.hpp b/pid/ec/stepwise.hpp
index ed07b44..4034b47 100644
--- a/pid/ec/stepwise.hpp
+++ b/pid/ec/stepwise.hpp
@@ -29,6 +29,8 @@
     float ts; // sample time in seconds
     float reading[maxStepwisePoints];
     float output[maxStepwisePoints];
+    float positiveHysteresis;
+    float negativeHysteresis;
 };
 
 float stepwise(const ec::StepwiseInfo& info, float value);