Added cranking enrich range (#335)

* First commit

Increases cranking enrichment range from 0..255% to 0..1275%, accuracy is reduced to 5% steps but this should be enough.

Max allowable gammae increased from 511% to 1500%, overflow in PW-function prevented.

* Last one missed the second overflow prevention (less bitshift)

* Version needs to be increased in order to avoid performing value update routine on every startup

* Less bitshift is required only on iCorrections

reference/speeduino.ini

@@ -896,7 +896,7 @@ page = 10
 #else
         crankingEnrichBins  = array,  U08,       0, [4],  "F",        1.8,    -22.23,    -40,    215,      0
 #endif
-        crankingEnrichValues= array,  U08,       4, [4],  "%",        1.0,    0.0,  0,    255,        0 ; Values for the cranking enrichment curve
+        crankingEnrichValues= array,  U08,       4, [4],  "%",        5.0,    0.0,  0,    1275,        0 ; Values for the cranking enrichment curve
 
         rotaryType          = bits ,  U08,       8, [0:1],           "FC", "FD", "RX8", "INVALID"
         stagingEnabled      = bits ,  U08,       8, [2:2],           "Off","On"
@@ -3030,7 +3030,7 @@ cmdtestspk450dc = "E\x03\x0C"
         curve = cranking_enrich_curve, "Cranking Enrichment Curve"
             columnLabel = "Coolant", "Fuel Modifier"
             xAxis       = -40, 110, 9
-            yAxis       =   0,  200, 6
+            yAxis       =   0,  400, 6
             xBins       = crankingEnrichBins, coolant
             yBins       = crankingEnrichValues
             ;gauge       = cltGau25

speeduino/corrections.h

@@ -9,7 +9,7 @@ void initialiseCorrections();
 
 uint16_t correctionsFuel();
 byte correctionWUE(); //Warmup enrichment
-byte correctionCranking(); //Cranking enrichment
+uint16_t correctionCranking(); //Cranking enrichment
 byte correctionASE(); //After Start Enrichment
 uint16_t correctionAccel(); //Acceleration Enrichment
 byte correctionFloodClear(); //Check for flood clear on cranking

speeduino/corrections.ino

@@ -48,7 +48,7 @@ uint16_t correctionsFuel()
   #define MAX_CORRECTIONS 3 //The maximum number of corrections allowed before the sum is reprocessed
   uint32_t sumCorrections = 100;
   byte activeCorrections = 0;
-  byte result; //temporary variable to store the result of each corrections function
+  uint16_t result; //temporary variable to store the result of each corrections function
 
   //The values returned by each of the correction functions are multipled together and then divided back to give a single 0-255 value.
   currentStatus.wueCorrection = correctionWUE();
@@ -104,7 +104,7 @@ uint16_t correctionsFuel()
 
   sumCorrections = sumCorrections / powint(100,activeCorrections);
 
-  if(sumCorrections > 511) { sumCorrections = 511; } //This is the maximum allowable increase as higher than this can potentially cause overflow in the PW() function (Can be fixed, but 511 is probably enough)
+  if(sumCorrections > 1500) { sumCorrections = 1500; } //This is the maximum allowable increase during cranking
   return (uint16_t)sumCorrections;
 }
 
@@ -176,13 +176,14 @@ byte correctionWUE()
 Cranking Enrichment
 Additional fuel % to be added when the engine is cranking
 */
-byte correctionCranking()
+uint16_t correctionCranking()
 {
-  byte crankingValue = 100;
+  uint16_t crankingValue = 100;
   //if ( BIT_CHECK(currentStatus.engine, BIT_ENGINE_CRANK) ) { crankingValue = 100 + configPage2.crankingPct; }
   if ( BIT_CHECK(currentStatus.engine, BIT_ENGINE_CRANK) )
   {
     crankingValue = table2D_getValue(&crankingEnrichTable, currentStatus.coolant + CALIBRATION_TEMPERATURE_OFFSET);
+    crankingValue = (uint16_t) crankingValue * 5; //multiplied by 5 to get range from 0% to 1275%
   }
   return crankingValue;
 }

speeduino/speeduino.ino

@@ -1140,6 +1140,12 @@ uint16_t PW(int REQ_FUEL, byte VE, long MAP, uint16_t corrections, int injOpen)
   uint16_t iAFR = 147;
 
   //100% float free version, does sacrifice a little bit of accuracy, but not much.
+
+  //If corrections are huge, use less bitshift to avoid overflow. Sacrifices a bit more accuracy (basically only during very cold temp cranking)
+  byte bitShift = 7;
+  if (corrections > 511 ) { bitShift = 6; }
+  if (corrections > 1023) { bitShift = 5; }
+  
   iVE = ((unsigned int)VE << 7) / 100;
   if ( configPage2.multiplyMAP == true ) {
     iMAP = ((unsigned int)MAP << 7) / currentStatus.baro;  //Include multiply MAP (vs baro) if enabled
@@ -1147,7 +1153,7 @@ uint16_t PW(int REQ_FUEL, byte VE, long MAP, uint16_t corrections, int injOpen)
   if ( (configPage2.includeAFR == true) && (configPage6.egoType == 2) && (currentStatus.runSecs > configPage6.ego_sdelay) ) {
     iAFR = ((unsigned int)currentStatus.O2 << 7) / currentStatus.afrTarget;  //Include AFR (vs target) if enabled
   }
-  iCorrections = (corrections << 7) / 100;
+  iCorrections = (corrections << bitShift) / 100;
 
 
   unsigned long intermediate = ((uint32_t)REQ_FUEL * (uint32_t)iVE) >> 7; //Need to use an intermediate value to avoid overflowing the long
@@ -1158,7 +1164,7 @@ uint16_t PW(int REQ_FUEL, byte VE, long MAP, uint16_t corrections, int injOpen)
     //EGO type must be set to wideband and the AFR warmup time must've elapsed for this to be used
     intermediate = (intermediate * (unsigned long)iAFR) >> 7;  
   }
-  intermediate = (intermediate * (unsigned long)iCorrections) >> 7;
+  intermediate = (intermediate * (unsigned long)iCorrections) >> bitShift;
   if (intermediate != 0)
   {
     //If intermeditate is not 0, we need to add the opening time (0 typically indicates that one of the full fuel cuts is active)

speeduino/updates.ino

@@ -10,7 +10,7 @@
 
 void doUpdates()
 {
-  #define CURRENT_DATA_VERSION    13
+  #define CURRENT_DATA_VERSION    14
 
   //May 2017 firmware introduced a -40 offset on the ignition table. Update that table to +40
   if(EEPROM.read(EEPROM_DATA_VERSION) == 2)
@@ -299,6 +299,19 @@ void doUpdates()
     EEPROM.write(EEPROM_DATA_VERSION, 13);
   }
 
+  if(EEPROM.read(EEPROM_DATA_VERSION) == 13)
+  {
+    //202003-dev
+    //Cranking enrichment range 0..1275% instead of older 0.255, so need to divide old values by 5
+    configPage10.crankingEnrichValues[0] = configPage10.crankingEnrichValues[0] / 5;
+    configPage10.crankingEnrichValues[1] = configPage10.crankingEnrichValues[1] / 5;
+    configPage10.crankingEnrichValues[2] = configPage10.crankingEnrichValues[2] / 5;
+    configPage10.crankingEnrichValues[3] = configPage10.crankingEnrichValues[3] / 5;
+    
+    writeAllConfig();
+    EEPROM.write(EEPROM_DATA_VERSION, 14);
+  }
+  
   //Final check is always for 255 and 0 (Brand new arduino)
   if( (EEPROM.read(EEPROM_DATA_VERSION) == 0) || (EEPROM.read(EEPROM_DATA_VERSION) == 255) )
   {