diff --git a/libraries/Desktop/include/wiring.h b/libraries/Desktop/include/wiring.h
index 5eb449f5e4..0b8710eef7 100644
--- a/libraries/Desktop/include/wiring.h
+++ b/libraries/Desktop/include/wiring.h
@@ -95,7 +95,7 @@ extern "C"{
 #define bitSet(value, bit) ((value) |= (1UL << (bit)))
 #define bitClear(value, bit) ((value) &= ~(1UL << (bit)))
 #define bitWrite(value, bit, bitvalue) (bitvalue ? bitSet(value, bit) : bitClear(value, bit))
-
+#define bit_is_set(value, bit) (((value) & bit) != 0)
 
 typedef unsigned int word;
 
@@ -109,7 +109,6 @@ void init(void);
 void pinMode(uint8_t, uint8_t);
 void digitalWrite(uint8_t, uint8_t);
 int digitalRead(uint8_t);
-int analogRead(uint8_t);
 void analogReference(uint8_t mode);
 void analogWrite(uint8_t, int);
 
diff --git a/libraries/Desktop/support/Arduino.cpp b/libraries/Desktop/support/Arduino.cpp
index 78f123577d..f82cc37e7c 100644
--- a/libraries/Desktop/support/Arduino.cpp
+++ b/libraries/Desktop/support/Arduino.cpp
@@ -129,11 +129,6 @@ void digitalWrite(uint8_t pin, uint8_t val)
 {
 }
 
-int analogRead(uint8_t pin)
-{
-	return 0;
-}
-
 }
 
 
diff --git a/libraries/Desktop/support/sitl.cpp b/libraries/Desktop/support/sitl.cpp
index ea774b83e9..069dbca932 100644
--- a/libraries/Desktop/support/sitl.cpp
+++ b/libraries/Desktop/support/sitl.cpp
@@ -268,6 +268,11 @@ static void timer_handler(int signum)
 			sitl.state.airspeed);
 	sitl_update_barometer(sitl.state.altitude);
 	sitl_update_compass(sitl.state.rollDeg, sitl.state.pitchDeg, sitl.state.heading);
+
+	// clear the ADC conversion flag,
+	// so the ADC code doesn't get stuck
+	ADCSRA &= ~_BV(ADSC);
+
 	sei();
 	running = false;
 }