Merge pull request #213 from jimwhitelaw/master

Fix for #211 Value returned by supportedPIDS_xx_xx() methods is off by one bit.
PowerBroker2 · Jan 2, 2024 · c2df64d · c2df64d
2 parents feaa1c0 + b378483
commit c2df64d
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Showing 2 changed files with 33 additions and 9 deletions.
diff --git a/src/ELMduino.cpp b/src/ELMduino.cpp
@@ -410,7 +410,7 @@ int8_t ELM327::nextIndex(char const *str,
  -------
   * float - Converted numerical value
 */
-float ELM327::conditionResponse(const uint8_t &numExpectedBytes, const float &scaleFactor, const float &bias)
+double ELM327::conditionResponse(const uint8_t &numExpectedBytes, const float &scaleFactor, const float &bias)
 {
     uint8_t numExpectedPayChars = numExpectedBytes * 2;
     uint8_t payCharDiff = numPayChars - numExpectedPayChars;
@@ -438,7 +438,17 @@ float ELM327::conditionResponse(const uint8_t &numExpectedBytes, const float &sc
         return 0;
     }
     else if (numExpectedPayChars == numPayChars)
-        return (response * scaleFactor) + bias;
+    {
+        if (scaleFactor == 1 && bias == 0) // No scale/bias needed
+        {
+            return response;
+        }
+        else 
+        {
+            return (response * scaleFactor) + bias;
+        }
+    }
+
 
     // If there were more payload bytes returned than we expected, test the first and last bytes in the
     // returned payload and see which gives us a higher value. Sometimes ELM327's return leading zeros
@@ -459,15 +469,29 @@ float ELM327::conditionResponse(const uint8_t &numExpectedBytes, const float &sc
     {
         if (debugMode)
             Serial.println("Lagging zeros found");
-
-        return ((float)(response >> (4 * payCharDiff)) * scaleFactor) + bias;
+        if (scaleFactor == 1 && bias == 0) // No scale/bias needed
+        {
+            return (response >> (4 * payCharDiff));
+        }
+        else 
+        {
+            return ((float)(response >> (4 * payCharDiff)) * scaleFactor) + bias;
+        }
+
     }
     else
     {
         if (debugMode)
             Serial.println("Lagging zeros not found - assuming leading zeros");
 
-        return (response * scaleFactor) + bias;
+        if (scaleFactor == 1 && bias == 0) // No scale/bias needed
+        {
+            return response;
+        }
+        else 
+        {
+            return (response * scaleFactor) + bias;
+        }
     }
 }
 
@@ -573,7 +597,7 @@ bool ELM327::queryPID(char queryStr[])
  -------
   * float - The PID value if successfully received, else 0.0
 */
-float ELM327::processPID(const uint8_t &service, const uint16_t &pid, const uint8_t &num_responses, const uint8_t &numExpectedBytes, const float &scaleFactor, const float &bias)
+double ELM327::processPID(const uint8_t &service, const uint16_t &pid, const uint8_t &num_responses, const uint8_t &numExpectedBytes, const float &scaleFactor, const float &bias)
 {
     if (nb_query_state == SEND_COMMAND)
     {
@@ -588,7 +612,7 @@ float ELM327::processPID(const uint8_t &service, const uint16_t &pid, const uint
             nb_query_state = SEND_COMMAND; // Reset the query state machine for next command
 
             findResponse();
-
+           
             return conditionResponse(numExpectedBytes, scaleFactor, bias);
         }
         else if (nb_rx_state != ELM_GETTING_MSG)

diff --git a/src/ELMduino.h b/src/ELMduino.h
@@ -318,12 +318,12 @@ class ELM327
 	uint64_t findResponse();
 	bool queryPID(const uint8_t& service, const uint16_t& pid, const uint8_t& num_responses = 1);
 	bool queryPID(char queryStr[]);
-	float processPID(const uint8_t& service, const uint16_t& pid, const uint8_t& num_responses, const uint8_t& numExpectedBytes, const float& scaleFactor = 1, const float& bias = 0);
+	double processPID(const uint8_t& service, const uint16_t& pid, const uint8_t& num_responses, const uint8_t& numExpectedBytes, const float& scaleFactor = 1, const float& bias = 0);
 	void sendCommand(const char *cmd);
 	int8_t sendCommand_Blocking(const char *cmd);
 	int8_t get_response();
 	bool timeout();
-	float conditionResponse(const uint8_t& numExpectedBytes, const float& scaleFactor = 1, const float& bias = 0);
+	double conditionResponse(const uint8_t& numExpectedBytes, const float& scaleFactor = 1, const float& bias = 0);
 
 	float batteryVoltage(void);
 	int8_t get_vin_blocking(char vin[]);