Oxides of nitrogen are adsorbed onto the surfaces of gas passages in a bed that has relative rotation with respect to a gas inlet distributor. The cap includes a crown and a headband in the form of a plurality of headband segments extending circumferentially along the lower peripheral edge of the crown of the cap. When a control message needs to be sent, the sequence of data message packets can be interrupted to send a control message packet. The method also generates a converted complementary memory block address identical to the other converted address except that bits in the bit locations more significant than the multi-block first bit location are the complements of the ending address bits.