A fairly common operation in communications is the sending of an ID over a radio channel to establish a secure link. One method to do this could be to use a serial EEPROM ( 128 bits typically) with an I2C interface and a Manchester encoder. The receiver has a decoder which recovers the signal, clock and data. A chip that can do these types of functions would be a really useful device. Except that a search on the web failed to yield a product like this. One or two semiconductor companies have Manchester encode/decode devices but they are prohibitively expensive in addition to not having the needed I2C interface, serial shift register etc. etc.. A PLD could be used to do these functions except that in volume the PLDs may not be competitive. Signal Processing Group Inc., has developed an encoder and decoder for manchester code based communications. Please contact Signal Processing Group Inc., at http://www.signalpro.biz for details.