code: function() {
  		var tndOut = 0, // triangle, noise, dmc
  			pulseOut = 0;
  
  		this.pulse1.doTimer();
  		this.pulse2.doTimer();
  		this.triangle.doTimer();
  		this.noise.doTimer();
  		this.dmc.doTimer();
  
  		if ( this.output.enabled ) {
  			// no need to do calculations if output is disabled
  			if ( this.sampleCounter >= this.sampleCounterMax ) {
  				pulseOut =  pulseTable[ this.pulse1.sample + this.pulse2.sample ];
  				tndOut = tndTable[ 3 * this.triangle.sample + 2 * this.noise.sample + this.dmc.sample ];
  
  				this.output.writeSample( pulseOut + tndOut );
  
  				this.sampleCounter -= this.sampleCounterMax;
  			}
  
  			this.sampleCounter += 1;
  		}
  	}
docs: Update output sample.