Support thermistor

Support thermistor readout, schematic see
http://iwantmyreal.name/blog/2012/09/23/measuring-the-temperature-with-an-arduino-and-a-thermistor/

Author: jenkie

Arduino_Pedelec_Controller/Arduino_Pedelec_Controller.ino

@@ -282,6 +282,10 @@ volatile boolean readtorque=false;  //true if torque array has been updated -> r
 unsigned long bbs_pausestart=0; //start time of power pause for gear change
 #endif
 
+#ifdef SUPPORT_THERMISTOR
+float temperature_thermistor=0; //thermistor temperature
+#endif
+
 #if (SERIAL_MODE & SERIAL_MODE_MMC)           //communicate with mmc-app
 String mmc_command="";
 byte mmc_value=0;
@@ -544,6 +548,10 @@ loadcell.tare();                   //set zero scale. remove any load diring star
 loadcell.set_scale(hx711_scale);   //apply scaling
 #endif
 
+#ifdef SUPPORT_THERMISTOR
+  pinMode(thermistor_pin,INPUT);
+#endif
+
 #ifdef DEBUG_MEMORY_USAGE
     Serial.print(MY_F("memFree after setup:"));
     Serial.print(memFree());
@@ -975,6 +983,10 @@ if (loadcell.is_ready())     //new conversion result from load cell available
         sensors.requestTemperatures(); // read temperature(s) from DS18x20 sensor. Readouts are in sensors.getTempCByIndex(n)
 #endif
 
+#ifdef SUPPORT_THERMISTOR
+       temperature_thermistor=1/(thermistor_t0+thermistor_b*log((10240/analogRead(thermistor_pin)-10)/thermistor_r))-273.15; //calculate thermistor temperature from Steinhart-Hart parameters
+#endif
+
         battery_percent_fromcapacity = constrain((1-wh/ curr_capacity)*100,0,100);     //battery percent calculation from battery capacity. For voltage-based calculation see above
         range=constrain(curr_capacity/wh*km-km,0.0,200.0);               //range calculation from battery capacity
         wh+=current*(millis()-last_writetime)/3600000.0*voltage;  //watthours calculation
@@ -1252,6 +1264,10 @@ void serial_debug(HardwareSerial* localSerial)
 #ifdef SUPPORT_TEMP_SENSOR
     localSerial->print(MY_F(" Temp"));
     localSerial->print(sensors.getTempCByIndex(0),2);
+#endif
+#ifdef SUPPORT_THERMISTOR
+    localSerial->print(MY_F(" Temp"));
+    localSerial->print(temperature_thermistor,1);
 #endif
     /*
         localSerial->print(MY_F(" TEMP"));

Arduino_Pedelec_Controller/config.h

@@ -175,6 +175,12 @@ const byte gear_shift_pin_high_gear = 7;     //pin that connects to the high gea
 //#define SUPPORT_TEMP_SENSOR                //uncomment if you want to use a DS18x20 temperature sensor
 const byte temp_pin = A2;                     //pin connected to Data pin of the DS18x20 temperature Sensor
 
+//#define SUPPORT_THERMISTOR                 //uncomment if you have thermistor connected
+const byte thermistor_pin = A2;              //thermistor pin
+const float thermistor_t0=0.00335401643;     // 1/T0 of thermistor in 1/K
+const float thermistor_b=0.00025316455;      // 1/beta of thermistor in 1/K
+const float thermistor_r=10;                 // r of thermistor in kOhm
+
 //#define SUPPORT_HX711                        //uncomment this if you want to use a load cell with hx711 amplifier
 const byte hx711_data=20;                    //data pin of hx711 sensor
 const byte hx711_sck=21;                     //clock pin of hx711 sensor

tools/compile_test.py

@@ -47,6 +47,7 @@
                   'SUPPORT_GEAR_SHIFT',
                   'SUPPORT_MOTOR_SERVO',
                   'SUPPORT_TEMP_SENSOR',
+				  'SUPPORT_THERMISTOR',
                   'SUPPORT_HX711',
                   'DETECT_BROKEN_SPEEDSENSOR',
                   'USE_EXTERNAL_CURRENT_SENSOR',
@@ -205,6 +206,10 @@ def write_config_h(filename=CONFIG_H,
         f.write('\n')
         f.write('//Config Options-----------------------------------------------------------------------------------------------------\n')
         f.write('const byte temp_pin = A2;                //pin connected to Data pin of the DS18x20 temperature Sensor\n')
+		f.write('const byte thermistor_pin = A2;              //thermistor pin\n')
+		f.write('const float thermistor_t0=0.00335401643;     // 1/T0 of thermistor in 1/K\n')
+		f.write('const float thermistor_b=0.00025316455;      // 1/beta of thermistor in 1/K\n')
+		f.write('const float thermistor_r=10;                 // r of thermistor in kOhm\n')
         f.write('const int pas_tolerance=1;               //0... increase to make pas sensor slower but more tolerant against speed changes\n')
         f.write('const int throttle_offset=196;           //Offset voltage of throttle control when in "0" position (0..1023 = 0..5V)\n')
         f.write('const int throttle_max=832;              //Offset voltage of throttle control when in "MAX" position (0..1023 = 0..5V)\n')
@@ -476,6 +481,7 @@ def test_max_config_fc2x0(self):
                             'SUPPORT_BATTERY_CHARGE_COUNTER',
                             'SUPPORT_GEAR_SHIFT',
                             'SUPPORT_TEMP_SENSOR',
+							'SUPPORT_THERMISTOR',
                             'SUPPORT_HX711',
                             'DETECT_BROKEN_SPEEDSENSOR'
                         ]