 				Update the controls if the update flag was set in the serialEvent1 callback.
 			*/
 			if(update_flag) {
+				//lock in case there are interrupts. 
 				acquireLock();
 				for(int i = 0; i < BUFFERSIZE; i++) {
 					throttle = buffer[0];

			#endif
			//run pids at 100Hz
			if(oneHunHzEvent.shouldRunEvent()) {
				computePID();
			}
			updateMotors();
			
			#ifdef DEBUG

}

/**
* Compute the next PIDs. 
*/
inline void computePID() {
	acquireLock();
