private byte getRegister4015(){
				boolean oldFrameInterruptFlag = _frameInterruptFlag;
				if(!_justSet){
					if(_frameInterruptFlag) {
				//		System.out.println("Clearing Interrupt 4015");
						_frameInterruptFlag = false; // need to handle a special case here
						//triggerCount = 0;
					}
				}
				byte b =
					(byte)((_dmcInterruptFlag    ? 0x80 : 0)
							| (oldFrameInterruptFlag      ? 0x40 : 0)
							| ((_dmcBytesRemaining > 0) ? 0x10 : 0)
							| ((volumeLengthCounter[NOISE] > 0)               ? 0x8  : 0)
							| ((volumeLengthCounter[TRIANGLE] > 0)            ? 0x4  : 0)
							| ((volumeLengthCounter[SQUARE2] > 0)             ? 0x2  : 0)
							| ((volumeLengthCounter[SQUARE1] > 0)             ? 0x1  : 0)
					);
				return b;
			}