comment headers, notes

firmware/controllers/algo/airmass/speed_density_base.cpp

@@ -1,3 +1,11 @@
+/**
+ * @file	speed_density_base.cpp
+ *
+ * Base for speed density (ie, ideal gas law) math shared by multiple fueling modes.
+ * 
+ * @date July 22, 2020
+ * @author Matthew Kennedy, (C) 2020
+ */
 
 #include "global.h"
 #include "speed_density_base.h"
@@ -5,13 +13,16 @@
 EXTERN_ENGINE;
 
 /**
- * is J/g*K
- * aka 
+ * Derived via:
+ * (8.31 J K mol^-1)  <- ideal gas constant R
+ * /
+ * (28.97g mol^-1)    <- molar mass of air
+ * = 0.28705 J*K/g
  */
-#define GAS_R 0.28705
+#define AIR_R 0.28705f
 
 float idealGasLaw(float volume, float pressure, float temperature) {
-	return volume * pressure / (GAS_R * temperature);
+	return volume * pressure / (AIR_R * temperature);
 }
 
 float SpeedDensityBase::getAirmassImpl(float ve, float manifoldPressure, float temperature DECLARE_ENGINE_PARAMETER_SUFFIX) {

firmware/controllers/algo/airmass/speed_density_base.h

@@ -1,3 +1,12 @@
+/**
+ * @file	speed_density_base.h
+ *
+ * Base for speed density (ie, ideal gas law) math shared by multiple fueling modes.
+ * 
+ * @date July 22, 2020
+ * @author Matthew Kennedy, (C) 2020
+ */
+
 #pragma once
 
 #include "engine.h"