public void decrease ( final DeviceControllerChannel channel , final int steps ) throws IOException { if ( channel == null ) { throw new RuntimeException ( "null-channel is not allowed. For devices " + "knowing just one wiper Channel.A is mandatory for " + "parameter 'channel'" ) ; } // decrease only works on volatile-wiper byte memAddr = channel . getVolatileMemoryAddress ( ) ; increaseOrDecrease ( memAddr , false , steps ) ; }
Decrements the volatile wiper for the given number steps .