added constructor

src/Battery.cpp

@@ -24,8 +24,16 @@ Battery::Battery(uint16_t minVoltage, uint16_t maxVoltage, uint8_t sensePin) {
 	this->activationPin = 0xFF;
 	this->minVoltage = minVoltage;
 	this->maxVoltage = maxVoltage;
+	readFunction = &analogRead;
 }
 
+Battery::Battery(uint16_t minVoltage, uint16_t maxVoltage, uint8_t sensePin, readFn_t readfunc)
+{
+	Battery(minVoltage, maxVoltage, sensePin);
+	readFunction = readfunc;
+}
+
+
 void Battery::begin(uint16_t refVoltage, float dividerRatio, mapFn_t mapFunction) {
 	this->refVoltage = refVoltage;
 	this->dividerRatio = dividerRatio;
@@ -64,9 +72,9 @@ uint16_t Battery::voltage() {
 		digitalWrite(activationPin, activationMode);
 		delayMicroseconds(10); // copes with slow switching activation circuits
 	}
-	analogRead(sensePin);
+	readFunction(sensePin);
 	delay(2); // allow the ADC to stabilize
-	uint16_t reading = analogRead(sensePin) * dividerRatio * refVoltage / 1024;
+	uint16_t reading = readFunction(sensePin) * dividerRatio * refVoltage / 1024;
 	if (activationPin != 0xFF) {
 		digitalWrite(activationPin, !activationMode);
 	}

src/Battery.h

@@ -22,6 +22,8 @@
 #include <Arduino.h>
 
 typedef uint8_t(*mapFn_t)(uint16_t, uint16_t, uint16_t);
+typedef uint16_t (*readFn_t)(uint8_t); // type for conciseness
+
 
 class Battery {
 	public:
@@ -35,6 +37,7 @@ class Battery {
 		 */
 		Battery(uint16_t minVoltage, uint16_t maxVoltage, uint8_t sensePin);
 
+		Battery(uint16_t minVoltage, uint16_t maxVoltage, uint8_t sensePin, readFn_t readfunc);
 		/**
 		 * Initializes the library by optionally setting additional parameters.
 		 * To obtain the best results use a calibrated reference using the VoltageReference library or equivalent.
@@ -81,6 +84,7 @@ class Battery {
 		uint8_t activationPin;
 		uint8_t activationMode;
 		mapFn_t mapFunction;
+		readFn_t readFunction;
 };
 
 //